diff --git a/MumbleChannelJoiner.cpp b/MumbleChannelJoiner.cpp
index 30ad1b1..4f58a7c 100644
--- a/MumbleChannelJoiner.cpp
+++ b/MumbleChannelJoiner.cpp
@@ -5,12 +5,20 @@ using namespace std;
 
 mumble::MumbleChannelJoiner::MumbleChannelJoiner(std::string channelNameRegex) : channelNameRegex(boost::regex(channelNameRegex)),
 logger(log4cpp::Category::getInstance("MumbleChannelJoiner")){
+    //std::vector<ChannelEntry> *channels = new std::vector<ChannelEntry>();
 }
 
+std::vector<mumble::MumbleChannelJoiner::ChannelEntry> mumble::MumbleChannelJoiner::channels;
+
 void mumble::MumbleChannelJoiner::checkChannel(std::string channel_name, int channel_id) {
     boost::smatch s;
+    ChannelEntry ent;
     logger.debug("Channel %s available (%d)", channel_name.c_str(), channel_id);
 
+    ent.name = channel_name;
+    ent.id = channel_id;
+
+    channels.push_back(ent);
 
     if(boost::regex_match(channel_name, s, channelNameRegex)) {
       this->channel_id = channel_id;
@@ -23,3 +31,22 @@ void mumble::MumbleChannelJoiner::maybeJoinChannel(mumble::MumbleCommunicator *m
 	}
 }
 
+/* This is a secondary channel-switching object that relys on updates to the
+ * class variable 'channels' for the channel list from the server.
+ */
+void mumble::MumbleChannelJoiner::findJoinChannel(mumble::MumbleCommunicator *mc) {
+    boost::smatch s;
+
+    int found = -1;
+
+    for(std::vector<ChannelEntry>::iterator it = channels.begin(); it != channels.end(); ++it) {
+        if(boost::regex_match(it->name, s, channelNameRegex)) {
+            found = it->id;
+        }
+    }
+
+	if(found > -1) {
+		mc->joinChannel(found);
+	}
+}
+
diff --git a/MumbleChannelJoiner.hpp b/MumbleChannelJoiner.hpp
index 356d022..1de5867 100644
--- a/MumbleChannelJoiner.hpp
+++ b/MumbleChannelJoiner.hpp
@@ -3,21 +3,30 @@
 #include <boost/noncopyable.hpp>
 #include <log4cpp/Category.hh>
 
+#include <vector>
 #include <string>
 #include <boost/regex.hpp>
 #include "MumbleCommunicator.hpp"
 
 namespace mumble {
     class MumbleChannelJoiner : boost::noncopyable {
+
+        struct ChannelEntry {
+            int id;
+            std::string name;
+        };
+
     public:
         MumbleChannelJoiner(std::string channelNameRegex);
 
         void checkChannel(std::string channel_name, int channel_id);
         void maybeJoinChannel(mumble::MumbleCommunicator *mc);
+        void findJoinChannel(mumble::MumbleCommunicator *mc);
 
     private:
         log4cpp::Category &logger;
         boost::regex channelNameRegex;
         int channel_id;
+        static std::vector<ChannelEntry> channels;
     };
 }
diff --git a/MumbleCommunicator.cpp b/MumbleCommunicator.cpp
index f52511b..ab115d2 100644
--- a/MumbleCommunicator.cpp
+++ b/MumbleCommunicator.cpp
@@ -9,13 +9,14 @@ namespace mumble {
         std::shared_ptr<mumlib::Mumlib> mum;
         MumbleCommunicator *communicator;
 
+        // called by Mumlib when receiving audio from mumble server 
         virtual void audio(
                 int target,
                 int sessionId,
                 int sequenceNumber,
                 int16_t *pcm_data,
                 uint32_t pcm_data_size) override {
-            communicator->onIncomingPcmSamples(sessionId, sequenceNumber, pcm_data, pcm_data_size);
+            communicator->onIncomingPcmSamples(communicator->callId, sessionId, sequenceNumber, pcm_data, pcm_data_size);
         }
 
         virtual void channelState(
@@ -39,6 +40,26 @@ namespace mumble {
             communicator->onServerSync();
         };
 
+        /*
+        virtual void onUserState(
+                int32_t session,
+                int32_t actor,
+                std::string name,
+                int32_t user_id,
+                int32_t channel_id,
+                int32_t mute,
+                int32_t deaf,
+                int32_t suppress,
+                int32_t self_mute,
+                int32_t self_deaf,
+                std::string comment,
+                int32_t priority_speaker,
+                int32_t recording
+                ) override {
+            communicator->onUserState();
+        };
+        */
+
     };
 }
 
@@ -60,8 +81,37 @@ void mumble::MumbleCommunicator::connect(MumbleCommunicatorConfig &config) {
     callback->communicator = this;
     callback->mum = mum;
 
-    mum->connect(config.host, config.port, config.user, config.password);
-    mum->self_deaf(1);
+    // IMPORTANT: comment these out when experimenting with onConnect
+    if ( ! MUM_DELAYED_CONNECT ) {
+        mum->connect(config.host, config.port, config.user, config.password);
+        if ( mumbleConf.autodeaf ) {
+            mum->sendUserState(mumlib::UserState::SELF_DEAF, true);
+        }
+    }
+}
+
+void mumble::MumbleCommunicator::onConnect() {
+    if ( MUM_DELAYED_CONNECT ) {
+        mum->connect(mumbleConf.host, mumbleConf.port, mumbleConf.user, mumbleConf.password);
+    }
+
+    if ( mumbleConf.comment.size() > 0 ) {
+        mum->sendUserState(mumlib::UserState::COMMENT, mumbleConf.comment);
+    }
+    if ( mumbleConf.autodeaf ) {
+        mum->sendUserState(mumlib::UserState::SELF_DEAF, true);
+    }
+}
+
+void mumble::MumbleCommunicator::onDisconnect() {
+    if ( MUM_DELAYED_CONNECT ) {
+        mum->disconnect();
+    } else {
+    }
+}
+
+void mumble::MumbleCommunicator::onCallerAuth() {
+    //onServerSync();
 }
 
 void mumble::MumbleCommunicator::sendPcmSamples(int16_t *samples, unsigned int length) {
@@ -76,21 +126,45 @@ void mumble::MumbleCommunicator::sendTextMessage(std::string message) {
     mum->sendTextMessage(message);
 }
 
+/*
+void mumble::MumbleCommunicator::onUserState(
+        int32_t session,
+        int32_t actor,
+        std::string name,
+        int32_t user_id,
+        int32_t channel_id,
+        int32_t mute,
+        int32_t deaf,
+        int32_t suppress,
+        int32_t self_mute,
+        int32_t self_deaf,
+        std::string comment,
+        int32_t priority_speaker,
+        int32_t recording) {
+
+    logger::notice("Entered onUserState(...)");
+
+    userState.mute = mute;
+    userState.deaf = deaf;
+    userState.suppress = suppress;
+    userState.self_mute = self_mute;
+    userState.self_deaf = self_deaf;
+    userState.priority_speaker = priority_speaker;
+    userState.recording = recording;
+}
+*/
+
+
 void mumble::MumbleCommunicator::joinChannel(int channel_id) {
     mum->joinChannel(channel_id);
+
     if ( mumbleConf.autodeaf ) {
-        //mum->self_mute(1);
-        mum->self_deaf(1);
+        mum->sendUserState(mumlib::UserState::SELF_DEAF, true);
     }
 }
 
-void mumble::MumbleCommunicator::mutedeaf(int status) {
-    if ( mumbleConf.autodeaf ) {
-        if ( status ) {
-            mum->self_deaf(status);
-        } else {
-            mum->self_mute(status);
-        }
-    }
+
+void mumble::MumbleCommunicator::sendUserState(mumlib::UserState field, bool val) {
+    mum->sendUserState(field, val);
 }
 
diff --git a/MumbleCommunicator.hpp b/MumbleCommunicator.hpp
index 8fef318..2ea5828 100644
--- a/MumbleCommunicator.hpp
+++ b/MumbleCommunicator.hpp
@@ -8,6 +8,9 @@
 #include <string>
 #include <stdexcept>
 
+// 0 = mumble users connected at start; 1 = connect at dial-in
+// TODO: fix mumlib::TransportException when this option is enabled
+#define MUM_DELAYED_CONNECT 0
 
 namespace mumble {
 
@@ -26,6 +29,20 @@ namespace mumble {
         int opusEncoderBitrate;
         int port = 0;
         bool autodeaf;
+        std::string comment;
+        int max_calls = 1;
+        std::string authchan; // config.ini: channelAuthExpression
+    };
+
+    // This is the subset that is of interest to us
+    struct MumbleUserState {
+        int32_t mute;
+        int32_t deaf;
+        int32_t suppress;
+        int32_t self_mute;
+        int32_t self_deaf;
+        int32_t priority_speaker;
+        int32_t recording;
     };
 
     class MumbleCommunicator : boost::noncopyable {
@@ -34,6 +51,10 @@ namespace mumble {
                 boost::asio::io_service &ioService);
 
         void connect(MumbleCommunicatorConfig &config);
+        void onConnect();
+        void onDisconnect();
+        void onCallerAuth();
+        //void onCallerUnauth();
 
         virtual ~MumbleCommunicator();
 
@@ -41,9 +62,9 @@ namespace mumble {
 
         /**
          * This callback is called when communicator has received samples.
-         * Arguments: session ID, sequence number, PCM samples, length of samples
+         * Arguments: call ID, session ID, sequence number, PCM samples, length of samples
          */
-        std::function<void(int, int, int16_t *, int)> onIncomingPcmSamples;
+        std::function<void(int, int, int, int16_t *, int)> onIncomingPcmSamples;
 
         /**
          * This callback is called when a channel state message (e.g. Channel
@@ -53,11 +74,17 @@ namespace mumble {
 
         std::function<void()> onServerSync;
 
+        std::function<void()> onUserState;
+
         void sendTextMessage(std::string message);
 
         void joinChannel(int channel_id);
 
-        void mutedeaf(int status);
+        void sendUserState(mumlib::UserState field, bool val);
+
+        MumbleUserState userState;
+
+        int callId;
 
     private:
         boost::asio::io_service &ioService;
diff --git a/PjsuaCommunicator.cpp b/PjsuaCommunicator.cpp
index 5d4d56d..abb02c5 100644
--- a/PjsuaCommunicator.cpp
+++ b/PjsuaCommunicator.cpp
@@ -6,6 +6,8 @@
 #include <boost/algorithm/string.hpp>
 #include <boost/format.hpp>
 
+#include "main.hpp"
+
 using namespace std;
 
 namespace sip {
@@ -38,9 +40,9 @@ namespace sip {
 
     class _MumlibAudioMedia : public pj::AudioMedia {
     public:
-        _MumlibAudioMedia(sip::PjsuaCommunicator &comm, int frameTimeLength)
+        _MumlibAudioMedia(int call_id, sip::PjsuaCommunicator &comm, int frameTimeLength)
                 : communicator(comm) {
-            createMediaPort(frameTimeLength);
+            createMediaPort(call_id, frameTimeLength);
             registerMediaPort(&mediaPort);
         }
 
@@ -62,7 +64,7 @@ namespace sip {
             return communicator->mediaPortPutFrame(port, frame);
         }
 
-        void createMediaPort(int frameTimeLength) {
+        void createMediaPort(int call_id, int frameTimeLength) {
 
             auto name = pj_str((char *) "MumsiMediaPort");
 
@@ -88,6 +90,8 @@ namespace sip {
             }
 
             mediaPort.port_data.pdata = &communicator;
+            // track call id in port_data
+            mediaPort.port_data.ldata = (long) call_id;
 
             mediaPort.get_frame = &callback_getFrame;
             mediaPort.put_frame = &callback_putFrame;
@@ -145,14 +149,19 @@ namespace sip {
         if (ci.state == PJSIP_INV_STATE_CONFIRMED) {
             auto msgText = "Incoming call from " + address + ".";
 
+            // first, login to Mumble (only matters if MUM_DELAYED_CONNECT)
+            communicator.calls[ci.id].onConnect();
+            pj_thread_sleep(500); // sleep a moment to allow connection to stabilize
+
             communicator.logger.notice(msgText);
-            communicator.onStateChange(msgText);
+            communicator.calls[ci.id].onStateChange(msgText);
 
             pj_thread_sleep(500); // sleep a moment to allow connection to stabilize
             this->playAudioFile(communicator.file_welcome);
 
             communicator.got_dtmf = "";
 
+            communicator.logger.notice("MYDEBUG: pin length=%d", communicator.caller_pin.length());
             /* 
              * if no pin is set, go ahead and turn off mute/deaf
              * otherwise, wait for pin to be entered
@@ -160,11 +169,18 @@ namespace sip {
             if ( communicator.caller_pin.length() == 0 ) {
                 // No PIN set... enter DTMF root menu and turn off mute/deaf
                 communicator.dtmf_mode = DTMF_MODE_ROOT;
-                communicator.onMuteDeafChange(0);
+                // turning off mute automatically turns off deaf
+                communicator.calls[ci.id].sendUserState(mumlib::UserState::SELF_MUTE, false);
+                pj_thread_sleep(500); // sleep a moment to allow connection to stabilize
+                this->playAudioFile(communicator.file_announce_new_caller, true);
             } else {
                 // PIN set... enter DTMF unauth menu and play PIN prompt message
                 communicator.dtmf_mode = DTMF_MODE_UNAUTH;
+                communicator.logger.notice("MYDEBUG: call joinDefaultChannel()");
+                communicator.calls[ci.id].joinDefaultChannel();
                 pj_thread_sleep(500); // pause briefly after announcement
+                communicator.logger.notice("MYDEBUG: call play...()");
+
                 this->playAudioFile(communicator.file_prompt_pin);
             }
 
@@ -174,16 +190,23 @@ namespace sip {
             if (not acc.available) {
                 auto msgText = "Call from " + address + " finished.";
 
-                communicator.mixer->clear();
+                communicator.calls[ci.id].mixer->clear();
 
                 communicator.logger.notice(msgText);
-                communicator.onStateChange(msgText);
-                communicator.onMuteDeafChange(1);
+                communicator.calls[ci.id].onStateChange(msgText);
+                communicator.calls[ci.id].sendUserState(mumlib::UserState::SELF_DEAF, true);
+                communicator.logger.notice("MYDEBUG: call joinDefaultChannel()");
+                communicator.calls[ci.id].joinDefaultChannel();
+
+                communicator.calls[ci.id].onDisconnect();
 
                 acc.available = true;
             }
 
             delete this;
+        } else {
+            communicator.logger.notice("MYDEBUG: onCallState() call:%d state:%d",
+                    ci.id, ci.state);
         }
     }
 
@@ -197,8 +220,8 @@ namespace sip {
         if (ci.media[0].status == PJSUA_CALL_MEDIA_ACTIVE) {
             auto *aud_med = static_cast<pj::AudioMedia *>(getMedia(0));
 
-            communicator.media->startTransmit(*aud_med);
-            aud_med->startTransmit(*communicator.media);
+            communicator.calls[ci.id].media->startTransmit(*aud_med);
+            aud_med->startTransmit(*communicator.calls[ci.id].media);
         } else if (ci.media[0].status == PJSUA_CALL_MEDIA_NONE) {
             dynamic_cast<_Account &>(account).available = true;
         }
@@ -244,14 +267,8 @@ namespace sip {
                 pinfo = player.getInfo();
                 sleeptime = pinfo.sizeBytes / (pinfo.payloadBitsPerSample * 3);
 
-                /*
-                communicator.logger.notice("DEBUG: wavsize=%d pbps=%d bytes=%d samples=%d", 
-                        wavsize, pinfo.payloadBitsPerSample, pinfo.sizeBytes, pinfo.sizeSamples);
-                communicator.logger.notice("WAVE length in ms: %d", sleeptime);
-                */
-
                 if ( in_chan ) { // choose the target sound output
-                    player.startTransmit(*communicator.media);
+                    player.startTransmit(*communicator.calls[ci.id].media);
                 } else {
                     player.startTransmit(*aud_med);
                 }
@@ -259,7 +276,7 @@ namespace sip {
                 pj_thread_sleep(sleeptime);
 
                 if ( in_chan ) { // choose the target sound output
-                    player.stopTransmit(*communicator.media);
+                    player.stopTransmit(*communicator.calls[ci.id].media);
                 } else {
                     player.stopTransmit(*aud_med);
                 }
@@ -277,6 +294,8 @@ namespace sip {
         //        prm.digit.c_str(), getId());
         pj::CallOpParam param;
 
+        auto ci = getInfo();
+
         /*
          * DTMF CALLER MENU
          */
@@ -295,8 +314,10 @@ namespace sip {
                             if ( communicator.got_dtmf == communicator.caller_pin ) {
                                 communicator.logger.notice("Caller entered correct PIN");
                                 communicator.dtmf_mode = DTMF_MODE_ROOT;
+                                communicator.calls[ci.id].joinAuthChannel();
+
                                 this->playAudioFile(communicator.file_entering_channel);
-                                communicator.onMuteDeafChange(0);
+                                communicator.calls[ci.id].sendUserState(mumlib::UserState::SELF_MUTE, false);
                                 this->playAudioFile(communicator.file_announce_new_caller, true);
                             } else {
                                 communicator.logger.notice("Caller entered wrong PIN");
@@ -357,18 +378,20 @@ namespace sip {
                  * User already entered '*'; time to perform action
                  */
                 switch ( prm.digit[0] ) {
-                    /*
                     case '5':
                         // Mute line
-                        communicator.onMuteChange(1);
+                        communicator.calls[ci.id].sendUserState(mumlib::UserState::SELF_MUTE, true);
                         this->playAudioFile(communicator.file_mute_on);
                         break;
                     case '6':
                         // Un-mute line
                         this->playAudioFile(communicator.file_mute_off);
-                        communicator.onMuteChange(0);
+                        communicator.calls[ci.id].sendUserState(mumlib::UserState::SELF_MUTE, false);
+                        break;
+                    case '0':
+                        // play menu
+                        this->playAudioFile(communicator.file_menu);
                         break;
-                     */
                     default:
                         communicator.logger.notice("Unsupported DTMF digit '%s' in state STAR", prm.digit.c_str());
                 }
@@ -405,7 +428,13 @@ namespace sip {
                 param.statusCode = PJSIP_SC_OK;
                 available = false;
             } else {
-                param.statusCode = PJSIP_SC_BUSY_EVERYWHERE;
+                /*
+                 * EXPERIMENT WITH MULTI-LINE
+                 */
+                communicator.logger.info("MULTI-LINE Incoming call from %s.", uri.c_str());
+                param.statusCode = PJSIP_SC_OK;
+                available = false;
+                //param.statusCode = PJSIP_SC_BUSY_EVERYWHERE;
             }
 
             call->answer(param);
@@ -417,18 +446,19 @@ namespace sip {
     }
 }
 
-sip::PjsuaCommunicator::PjsuaCommunicator(IncomingConnectionValidator &validator, int frameTimeLength)
+sip::PjsuaCommunicator::PjsuaCommunicator(IncomingConnectionValidator &validator, int frameTimeLength, int maxCalls)
         : logger(log4cpp::Category::getInstance("SipCommunicator")),
           pjsuaLogger(log4cpp::Category::getInstance("Pjsua")),
           uriValidator(validator) {
 
     logWriter.reset(new sip::_LogWriter(pjsuaLogger));
 
+
     endpoint.libCreate();
 
     pj::EpConfig endpointConfig;
     endpointConfig.uaConfig.userAgent = "Mumsi Mumble-SIP gateway";
-    endpointConfig.uaConfig.maxCalls = 1;
+    endpointConfig.uaConfig.maxCalls = maxCalls;
 
     endpointConfig.logConfig.writer = logWriter.get();
     endpointConfig.logConfig.level = 5;
@@ -437,11 +467,12 @@ sip::PjsuaCommunicator::PjsuaCommunicator(IncomingConnectionValidator &validator
 
     endpoint.libInit(endpointConfig);
 
-    pj_caching_pool_init(&cachingPool, &pj_pool_factory_default_policy, 0);
-
-    mixer.reset(new mixer::AudioFramesMixer(cachingPool.factory));
-
-    media.reset(new _MumlibAudioMedia(*this, frameTimeLength));
+    for(int i=0; i<maxCalls; ++i) {
+        calls[i].index = i;
+        pj_caching_pool_init(&(calls[i].cachingPool), &pj_pool_factory_default_policy, 0);
+        calls[i].mixer.reset(new mixer::AudioFramesMixer(calls[i].cachingPool.factory));
+        calls[i].media.reset(new _MumlibAudioMedia(i, *this, frameTimeLength));
+    }
 
     logger.info("Created Pjsua communicator with frame length %d ms.", frameTimeLength);
 }
@@ -472,8 +503,8 @@ sip::PjsuaCommunicator::~PjsuaCommunicator() {
     endpoint.libDestroy();
 }
 
-void sip::PjsuaCommunicator::sendPcmSamples(int sessionId, int sequenceNumber, int16_t *samples, unsigned int length) {
-    mixer->addFrameToBuffer(sessionId, sequenceNumber, samples, length);
+void sip::PjsuaCommunicator::sendPcmSamples(int callId, int sessionId, int sequenceNumber, int16_t *samples, unsigned int length) {
+    calls[callId].mixer->addFrameToBuffer(sessionId, sequenceNumber, samples, length);
 }
 
 pj_status_t sip::PjsuaCommunicator::mediaPortGetFrame(pjmedia_port *port, pjmedia_frame *frame) {
@@ -481,7 +512,8 @@ pj_status_t sip::PjsuaCommunicator::mediaPortGetFrame(pjmedia_port *port, pjmedi
     pj_int16_t *samples = static_cast<pj_int16_t *>(frame->buf);
     pj_size_t count = frame->size / 2 / PJMEDIA_PIA_CCNT(&(port->info));
 
-    const int readSamples = mixer->getMixedSamples(samples, count);
+    int call_id = (int) port->port_data.ldata;
+    const int readSamples = calls[call_id].mixer->getMixedSamples(samples, count);
 
     if (readSamples < count) {
         pjsuaLogger.debug("Requested %d samples, available %d, filling remaining with zeros.",
@@ -500,9 +532,11 @@ pj_status_t sip::PjsuaCommunicator::mediaPortPutFrame(pjmedia_port *port, pjmedi
     pj_size_t count = frame->size / 2 / PJMEDIA_PIA_CCNT(&port->info);
     frame->type = PJMEDIA_FRAME_TYPE_AUDIO;
 
+    int call_id = (int) port->port_data.ldata;
+
     if (count > 0) {
-        pjsuaLogger.debug("Calling onIncomingPcmSamples with %d samples.", count);
-        onIncomingPcmSamples(samples, count);
+        pjsuaLogger.debug("Calling onIncomingPcmSamples with %d samples (call_id=%d).", count, call_id);
+        this->calls[call_id].onIncomingPcmSamples(samples, count);
     }
 
     return PJ_SUCCESS;
diff --git a/PjsuaCommunicator.hpp b/PjsuaCommunicator.hpp
index bd69979..3ee0113 100644
--- a/PjsuaCommunicator.hpp
+++ b/PjsuaCommunicator.hpp
@@ -18,6 +18,11 @@
 #include <climits>
 #include <bits/unique_ptr.h>
 
+// for userState enum
+#include <mumlib.hpp>
+
+#include "main.hpp"
+
 enum dtmf_modes_t {DTMF_MODE_UNAUTH, DTMF_MODE_ROOT, DTMF_MODE_STAR};
 
 namespace sip {
@@ -62,9 +67,25 @@ namespace sip {
 
     class _MumlibAudioMedia;
 
+    struct call {
+        unsigned index;
+        std::unique_ptr<mixer::AudioFramesMixer> mixer;
+        std::unique_ptr<sip::_MumlibAudioMedia> media;
+        pj_caching_pool cachingPool;
+        std::function<void(std::string)> onStateChange;
+        std::function<void(int16_t *, int)> onIncomingPcmSamples;
+        std::function<void(int)> onMuteDeafChange;
+        std::function<void(mumlib::UserState field, bool val)> sendUserState;
+        std::function<void()> onConnect;
+        std::function<void()> onDisconnect;
+        std::function<void()> onCallerAuth;
+        std::function<void()> joinAuthChannel;
+        std::function<void()> joinDefaultChannel;
+    };
+
     class PjsuaCommunicator : boost::noncopyable {
     public:
-        PjsuaCommunicator(IncomingConnectionValidator &validator, int frameTimeLength);
+        PjsuaCommunicator(IncomingConnectionValidator &validator, int frameTimeLength, int maxCalls);
 
         void connect(
                 std::string host,
@@ -75,6 +96,7 @@ namespace sip {
         virtual ~PjsuaCommunicator();
 
         void sendPcmSamples(
+                int callId,
                 int sessionId,
                 int sequenceNumber,
                 int16_t *samples,
@@ -97,29 +119,18 @@ namespace sip {
         dtmf_modes_t dtmf_mode = DTMF_MODE_ROOT;
         int pin_fails = 0;
 
-        std::function<void(int16_t *, int)> onIncomingPcmSamples;
-
-        std::function<void(std::string)> onStateChange;
-
-        std::function<void(int)> onMuteDeafChange;
-
-        std::function<void(int)> onMuteChange;
-
         pj_status_t mediaPortGetFrame(pjmedia_port *port, pjmedia_frame *frame);
 
         pj_status_t mediaPortPutFrame(pjmedia_port *port, pjmedia_frame *frame);
 
+        call calls[MY_MAX_CALLS];
+
     private:
         log4cpp::Category &logger;
         log4cpp::Category &pjsuaLogger;
 
-        std::unique_ptr<mixer::AudioFramesMixer> mixer;
-
         std::unique_ptr<_LogWriter> logWriter;
         std::unique_ptr<_Account> account;
-        std::unique_ptr<_MumlibAudioMedia> media;
-
-        pj_caching_pool cachingPool;
 
         pj::Endpoint endpoint;
 
diff --git a/README.md b/README.md
index 9a3dd99..d1b11e8 100644
--- a/README.md
+++ b/README.md
@@ -47,6 +47,91 @@ Remember to add URIs which you want to make calls from. Calls from other URIs wo
 ./mumsi config.ini
 ```
 
+## Configuring
+
+### Multi-Line Support
+
+If your SIP provider allows multiple simultaneous calls, mumsi can be configured to accept
+calls and map them to separate Mumble users. The max\_calls is configure in *config.ini*:
+
+```
+[sip]
+...
+max_calls = 32
+...
+```
+
+Currently, the Mumble connections are established at server start. For usability, the following
+options are recommended:
+
+* caller\_pin
+* autodeaf
+* channelAuthExpression
+
+The maximum number of calls is set in *main.hpp* and should not exceed the
+*PJSUA_MAX_CALLS* in *pjsua.h*, which by default is 32. This can also be recompiled to
+more, if desired.
+
+When mumsi logs into Mumble, it uses the user name from *config.ini* and appends 
+the character '-', followed by the connection number (counter).
+
+*LIMITATIONS:* The code is _alpha_ and needs testing/debugging, especialy in
+the code that uses mumlib::Transport. Also, there is initial work on connecting
+the Mumble user only when the SIP call is active, so the UI for other users is 
+better, but this code is still very buggy and therefore disabled.
+
+### Caller PIN
+
+When the caller\_pin is set, the incoming SIP connection is mute/deaf until the
+caller enters the correct PIN, followed by the '#' symbol. On three failed 
+attempts, the SIP connection is hung up. On success, the Mumble user is moved
+into the channel matching channelAuthExpression, if specified, and then mute/deaf
+is turned off. As a courtesy to the other users, a brief announcement audio
+file is played in the Mumble channel.
+
+The caller\_pin is configured in *config.ini* in the *app* section:
+
+```
+[app]
+caller_pin = 12345
+```
+
+In addition to the caller\_pin, a channelAuthExpression can be set. After
+the caller authenticates with the PIN, the mumsi Mumble user will switch
+to the Mumble channel that matches this expression. When the call is
+completed, the mumsi Mumble user will return to the default channel that
+matches channelNameExpression.
+
+This helps keep the unused SIP connections from cluttering your channel.
+
+### Autodeaf
+
+By default (i.e. autodeaf=0), other Mumble users can only see whether the mumsi
+connection has an active caller if they are in the same channel. This is becaue
+the 'talking mouth' icon is not visible to users in other channels. The mute/deaf
+icons, on the other hand, can be seen by Mumble users when they are in different
+channels, making it easier to spot when a new caller has connected.
+
+Setting `autodeaf=1' causes the mumsi Mumble user to be mute/deaf when there
+is no active SIP call.
+
+### Audio Files
+
+When certain events occur, it is user-friendly to provide some sort of prompting
+confirmation to the user. An example set of WAV files is provided, but they
+can easily be customized or replaced with local versions, if needed. If the
+files are not found, no sound is played. The following events are supported:
+
+- welcome: Played to caller when first connecting to mumsi
+- prompt\_pin: Prompt the caller to enter the PIN
+- entering\_channel: Caller entered PIN and is now entering the Mumble channel
+- announce\_new\_caller: Played to the Mumble channel when adding a new caller
+- invalid\_pin: Let the caller know they entered the wrong PIN
+- goodbye: Hanging up on the caller
+- mute\_on: Self-mute has been turned on (not implemented)
+- mute\_off: Self-mute has been turned off (not implemented)
+- menu: Tell caller the menu options (not implemented)
+
 ## Start at boot
 
 *mumsi* provides no *init.d* scripts, but you can use great daemon mangaer, [Supervisor](http://supervisord.org/).
@@ -65,7 +150,6 @@ stdout_capture_maxbytes=1MB
 redirect_stderr=true
 ```
 
-
 ## Issues
 
 #### Port and NAT
@@ -82,6 +166,12 @@ pjsua_conf_add_port(mediaPool, (pjmedia_port *)port, &id) error: Invalid operati
 
 Some older versions of PJSIP are affected (confirmed for 2.3). In this case you have to update PJSIP to most recent version (2.4.5).
 
+#### mumlib::TrasportException
+
+The multi-caller code is _alpha_ and needs testing/debugging, especialy in
+the code that uses mumlib::Transport. Also, there is initial work on connecting
+the Mumble user only when the SIP call is active, so the UI for other users is 
+better, but this code is still very buggy and therefore disabled.
 
 ## TODO:
 
diff --git a/main.cpp b/main.cpp
index 8396f49..d76b6f0 100644
--- a/main.cpp
+++ b/main.cpp
@@ -10,6 +10,8 @@
 
 #include <execinfo.h>
 
+#include "main.hpp"
+
 /*
  * Code from http://stackoverflow.com/a/77336/5419223
  */
@@ -26,13 +28,15 @@ static void sigsegv_handler(int sig) {
 
 int main(int argc, char *argv[]) {
     signal(SIGSEGV, sigsegv_handler);
+    int max_calls;
 
     log4cpp::OstreamAppender appender("console", &std::cout);
     log4cpp::PatternLayout layout;
     layout.setConversionPattern("%d [%p] %c: %m%n");
     appender.setLayout(&layout);
     log4cpp::Category &logger = log4cpp::Category::getRoot();
-    logger.setPriority(log4cpp::Priority::NOTICE);
+    logger.setPriority(log4cpp::Priority::DEBUG);
+    //logger.setPriority(log4cpp::Priority::NOTICE);
     logger.addAppender(appender);
 
     if (argc == 1) {
@@ -48,40 +52,13 @@ int main(int argc, char *argv[]) {
 
     boost::asio::io_service ioService;
 
-    sip::PjsuaCommunicator pjsuaCommunicator(connectionValidator, conf.getInt("sip.frameLength"));
+    try {
+        max_calls = conf.getInt("sip.max_calls");
+    } catch (...) {
+        max_calls = 1;
+    }
 
-    mumble::MumbleCommunicator mumbleCommunicator(ioService);
-
-    mumble::MumbleChannelJoiner mumbleChannelJoiner(conf.getString("mumble.channelNameExpression"));
-
-    using namespace std::placeholders;
-    pjsuaCommunicator.onIncomingPcmSamples = std::bind(
-            &mumble::MumbleCommunicator::sendPcmSamples,
-            &mumbleCommunicator,
-            _1, _2);
-
-    pjsuaCommunicator.onStateChange = std::bind(
-            &mumble::MumbleCommunicator::sendTextMessage,
-            &mumbleCommunicator, _1);
-
-    pjsuaCommunicator.onMuteDeafChange = std::bind(
-            &mumble::MumbleCommunicator::mutedeaf,
-            &mumbleCommunicator, _1);
-
-    mumbleCommunicator.onIncomingPcmSamples = std::bind(
-            &sip::PjsuaCommunicator::sendPcmSamples,
-            &pjsuaCommunicator,
-            _1, _2, _3, _4);
-
-    mumbleCommunicator.onIncomingChannelState = std::bind(
-            &mumble::MumbleChannelJoiner::checkChannel,
-            &mumbleChannelJoiner,
-            _1, _2);
-
-    mumbleCommunicator.onServerSync = std::bind(
-            &mumble::MumbleChannelJoiner::maybeJoinChannel,
-            &mumbleChannelJoiner,
-            &mumbleCommunicator);
+    sip::PjsuaCommunicator pjsuaCommunicator(connectionValidator, conf.getInt("sip.frameLength"), max_calls);
 
     mumble::MumbleCommunicatorConfig mumbleConf;
     mumbleConf.host = conf.getString("mumble.host");
@@ -96,6 +73,18 @@ int main(int argc, char *argv[]) {
         mumbleConf.autodeaf = false;
     }
 
+    try {
+        mumbleConf.comment = conf.getString("app.comment");
+    } catch (...) {
+        mumbleConf.comment = "";
+    }
+
+    try {
+        mumbleConf.authchan = conf.getString("mumble.channelAuthExpression");
+    } catch (...) {
+        mumbleConf.authchan = "";
+    }
+
     /* default to <no pin> */
     try {
         pjsuaCommunicator.caller_pin = conf.getString("app.caller_pin");
@@ -148,7 +137,111 @@ int main(int argc, char *argv[]) {
         pjsuaCommunicator.file_menu = "menu.wav";
     }
 
-    mumbleCommunicator.connect(mumbleConf);
+    /* If the channelUnauthExpression is set, use this as the default
+     * channel and use channelNameExpression for the authchan. Otherwise,
+     * use the channelNameExpression for the default.
+     */
+    std::string defaultChan = conf.getString("mumble.channelNameExpression"); 
+    std::string authChan = "";
+
+    if ( pjsuaCommunicator.caller_pin.size() > 0 ) {
+        try {
+            authChan = conf.getString("mumble.channelAuthExpression");
+        } catch (...) {
+        //    defaultChan = conf.getString("mumble.channelNameExpression"); 
+        }
+    }
+
+    mumble::MumbleChannelJoiner mumbleChannelJoiner(defaultChan);
+    mumble::MumbleChannelJoiner mumbleAuthChannelJoiner(authChan);
+
+    for (int i = 0; i<max_calls; i++) {
+
+        auto *mumcom = new mumble::MumbleCommunicator(ioService);
+        mumcom->callId = i;
+
+        using namespace std::placeholders;
+        // Passing audio input from SIP to Mumble
+        pjsuaCommunicator.calls[i].onIncomingPcmSamples = std::bind(
+                &mumble::MumbleCommunicator::sendPcmSamples,
+                mumcom,
+                _1, _2);
+
+        // PJ sends text message to Mumble
+        pjsuaCommunicator.calls[i].onStateChange = std::bind(
+                &mumble::MumbleCommunicator::sendTextMessage,
+                mumcom,
+                _1);
+
+        /*
+        // Send mute/deaf to Mumble
+        pjsuaCommunicator.calls[i].onMuteDeafChange = std::bind(
+                &mumble::MumbleCommunicator::mutedeaf,
+                mumcom,
+                _1);
+         */
+
+        // Send UserState to Mumble
+        pjsuaCommunicator.calls[i].sendUserState = std::bind(
+                &mumble::MumbleCommunicator::sendUserState,
+                mumcom,
+                _1, _2);
+
+        // PJ triggers Mumble connect
+        pjsuaCommunicator.calls[i].onConnect = std::bind(
+                &mumble::MumbleCommunicator::onConnect,
+                mumcom);
+
+        // PJ triggers Mumble disconnect
+        pjsuaCommunicator.calls[i].onDisconnect = std::bind(
+                &mumble::MumbleCommunicator::onDisconnect,
+                mumcom);
+
+        // PJ notifies Mumble that Caller Auth is done
+        pjsuaCommunicator.calls[i].onCallerAuth = std::bind(
+                &mumble::MumbleCommunicator::onCallerAuth,
+                mumcom);
+
+        /*
+        // PJ notifies Mumble that Caller Auth is done
+        pjsuaCommunicator.calls[i].onCallerUnauth = std::bind(
+                &mumble::MumbleCommunicator::onCallerUnauth,
+                mumcom);
+                */
+
+        // PJ notifies Mumble that Caller Auth is done
+        pjsuaCommunicator.calls[i].joinDefaultChannel = std::bind(
+                &mumble::MumbleChannelJoiner::findJoinChannel,
+                &mumbleChannelJoiner,
+                mumcom);
+
+        // PJ notifies Mumble that Caller Auth is done
+        pjsuaCommunicator.calls[i].joinAuthChannel = std::bind(
+                &mumble::MumbleChannelJoiner::findJoinChannel,
+                &mumbleAuthChannelJoiner,
+                mumcom);
+
+        // Passing audio from Mumble to SIP
+        mumcom->onIncomingPcmSamples = std::bind(
+                &sip::PjsuaCommunicator::sendPcmSamples,
+                &pjsuaCommunicator,
+                _1, _2, _3, _4, _5);
+
+        // Handle Channel State messages from Mumble
+        mumcom->onIncomingChannelState = std::bind(
+                &mumble::MumbleChannelJoiner::checkChannel,
+                &mumbleChannelJoiner,
+                _1, _2);
+
+        // Handle Server Sync message from Mumble
+        mumcom->onServerSync = std::bind(
+                &mumble::MumbleChannelJoiner::maybeJoinChannel,
+                &mumbleChannelJoiner,
+                mumcom);
+
+        mumbleConf.user = conf.getString("mumble.user") + '-' + std::to_string(i);
+        mumcom->connect(mumbleConf);
+    }
 
     pjsuaCommunicator.connect(
             conf.getString("sip.host"),
diff --git a/main.hpp b/main.hpp
new file mode 100644
index 0000000..501350c
--- /dev/null
+++ b/main.hpp
@@ -0,0 +1,6 @@
+#pragma once
+
+// IMPORTANT: The default PJSUA_MAX_CALLS in pjsua.h is 32.
+// If you need more, you'll need to re-compile pjsua, too.
+//
+#define MY_MAX_CALLS 32
diff --git a/media/prompt-pin.msg b/media/prompt-pin.msg
index 75a9622..b64d9b8 100644
--- a/media/prompt-pin.msg
+++ b/media/prompt-pin.msg
@@ -1 +1 @@
-Please enter pin
+Please enter pin, followed by the hash symbol
diff --git a/media/prompt-pin.wav b/media/prompt-pin.wav
index d3a6ebd..fe5eecf 100644
Binary files a/media/prompt-pin.wav and b/media/prompt-pin.wav differ