diff --git a/ts3-client/core/src/main/java/com/ts3client/net/TeamspeakConnection.java b/ts3-client/core/src/main/java/com/ts3client/net/TeamspeakConnection.java
index eec84bc..26875ec 100644
--- a/ts3-client/core/src/main/java/com/ts3client/net/TeamspeakConnection.java
+++ b/ts3-client/core/src/main/java/com/ts3client/net/TeamspeakConnection.java
@@ -90,19 +90,23 @@ public final class TeamspeakConnection implements TS3Listener {
     final BanAdmin bans = new BanAdmin(this);
     private final AvatarAdmin avatarAdmin = new AvatarAdmin(this);
 
+    /*
+     * Set up by the connect thread and torn down by whichever thread notices the end; read from
+     * the UI, event and action threads, so each reader copies the field before using it.
+     */
     /** Package-private: read directly by {@link ConnectionStatsCollector}. */
-    LocalTeamspeakClientSocket client;
-    private VoiceInput microphone;
-    private VoiceOutput playback;
-    private LocalIdentity identity;
-    private FileTransferManager fileTransfers;
-    private ChatLogStore chatLogs;
+    volatile LocalTeamspeakClientSocket client;
+    private volatile VoiceInput microphone;
+    private volatile VoiceOutput playback;
+    private volatile LocalIdentity identity;
+    private volatile FileTransferManager fileTransfers;
+    private volatile ChatLogStore chatLogs;
     /**
      * Runs ts3j's event callbacks. Supplying it ourselves (rather than leaving ts3j to make
      * its own) is what lets {@link #awaitEventsProcessed()} tell when everything the server
      * has already sent has been handled. Closed together with the socket.
      */
-    private ExecutorService eventExecutor;
+    private volatile ExecutorService eventExecutor;
     /** Runs this connection's requests to the server; created on connect, shut down with the socket. */
     private volatile ExecutorService actions;
 
@@ -248,6 +252,9 @@ public final class TeamspeakConnection implements TS3Listener {
                            String channel, String channelPassword) {
         Object attempt = new Object();
         connectAttempt = attempt;
+        // A socket or audio line an earlier connect left behind must not outlive it.
+        connected = false;
+        safeCleanup();
         try {
             identity = withIdentity;
             serverHost = address;
@@ -570,7 +577,8 @@ public final class TeamspeakConnection implements TS3Listener {
     // ---- self actions ----
 
     public void setMicMuted(boolean muted) {
-        if (microphone != null) microphone.setMuted(muted);
+        VoiceInput mic = microphone;
+        if (mic != null) mic.setMuted(muted);
         sound(muted ? SoundEvent.SOUND_CAPTURE_MUTED : SoundEvent.SOUND_CAPTURE_UNMUTED);
         pushSelfFlags();
     }
@@ -580,22 +588,26 @@ public final class TeamspeakConnection implements TS3Listener {
      * status the server (and other clients) see, and without a mute/unmute sound.
      */
     public void setMicLocalMuted(boolean muted) {
-        if (microphone != null) microphone.setLocalMuted(muted);
+        VoiceInput mic = microphone;
+        if (mic != null) mic.setLocalMuted(muted);
     }
 
     public void setDeafened(boolean deaf) {
         // Announce muting while we can still be heard, and unmuting once we can again.
         if (deaf) sound(SoundEvent.SOUND_PLAYBACK_MUTED);
         deafened = deaf;
-        if (playback != null) playback.setDeafened(deaf);
+        VoiceOutput out = playback;
+        if (out != null) out.setDeafened(deaf);
         if (!deaf) sound(SoundEvent.SOUND_PLAYBACK_UNMUTED);
         pushSelfFlags();
     }
 
     private void pushSelfFlags() {
-        if (microphone == null || playback == null) return;
-        boolean micMuted = microphone.isMuted();
-        boolean deaf = playback.isDeafened();
+        VoiceInput mic = microphone;
+        VoiceOutput out = playback;
+        if (mic == null || out == null) return;
+        boolean micMuted = mic.isMuted();
+        boolean deaf = out.isDeafened();
         updateSelf(self -> {
             self.inputMuted = micMuted;
             self.outputMuted = deaf;
@@ -815,7 +827,8 @@ public final class TeamspeakConnection implements TS3Listener {
 
     public double getPingMillis() {
         try {
-            return client != null ? client.getPing().getKey() * 1000.0 : -1;
+            LocalTeamspeakClientSocket sock = client;
+            return sock != null ? sock.getPing().getKey() * 1000.0 : -1;
         } catch (Exception e) {
             return -1;
         }
@@ -972,9 +985,10 @@ public final class TeamspeakConnection implements TS3Listener {
     private Contact applyContactPlayback(ClientEntry client) {
         if (client == null || client.self) return null;
         Contact contact = contacts.find(client.uniqueId);
-        if (contact != null && playback != null) {
-            if (contact.automute) playback.setClientMuted(client.id, true);
-            playback.setClientVolume(client.id, contact.volumeGain());
+        VoiceOutput out = playback;
+        if (contact != null && out != null) {
+            if (contact.automute) out.setClientMuted(client.id, true);
+            out.setClientVolume(client.id, contact.volumeGain());
         }
         return contact;
     }
@@ -991,7 +1005,8 @@ public final class TeamspeakConnection implements TS3Listener {
 
     /** Remembers a per-client volume, in the contact entry when the client has one. */
     public void setClientVolumeModifier(ClientEntry client, double decibels) {
-        if (playback != null) playback.setClientVolume(client.id, Math.pow(10.0, decibels / 20.0));
+        VoiceOutput out = playback;
+        if (out != null) out.setClientVolume(client.id, Math.pow(10.0, decibels / 20.0));
         Contact contact = contacts.find(client.uniqueId);
         if (contact == null) return;
         contact.hasVolumeModifier = decibels != 0;
@@ -1000,8 +1015,9 @@ public final class TeamspeakConnection implements TS3Listener {
     }
 
     public double getClientVolumeModifier(ClientEntry client) {
-        if (playback == null) return 0;
-        double gain = playback.getClientVolume(client.id);
+        VoiceOutput out = playback;
+        if (out == null) return 0;
+        double gain = out.getClientVolume(client.id);
         return gain <= 0 ? -60 : 20.0 * Math.log10(gain);
     }