diff --git a/audiobuffer.cpp b/audiobuffer.cpp
index 354aabf15..80680d963 100644
--- a/audiobuffer.cpp
+++ b/audiobuffer.cpp
@@ -34,3 +34,8 @@ qint64 AudioBuffer::bufferSize() const
 {
     return buffer.size();
 }
+
+void AudioBuffer::clear()
+{
+    buffer.clear();
+}
diff --git a/audiobuffer.h b/audiobuffer.h
index 5041cc3f6..b5a4b736e 100644
--- a/audiobuffer.h
+++ b/audiobuffer.h
@@ -15,6 +15,7 @@ public:
     qint64 writeData(const char *data, qint64 len);
     qint64 bytesAvailable() const;
     qint64 bufferSize() const;
+    void clear();
 
 private:
     QByteArray buffer;
diff --git a/core.cpp b/core.cpp
index a2649d4ab..77a76001c 100644
--- a/core.cpp
+++ b/core.cpp
@@ -1056,17 +1056,19 @@ void Core::prepareCall(int friendId, int callId, ToxAv* toxav)
     }
     else
         qDebug() << QString("Core: Audio started, buffer size %1").arg(calls[callId].audioOutput->bufferSize());
-    QtConcurrent::run(playCallAudio, callId, toxav);
+    calls[callId].playFuture = QtConcurrent::run(playCallAudio, callId, toxav);
 }
 
 void Core::cleanupCall(int callId)
 {
     qDebug() << QString("Core: cleaning up call %1").arg(callId);
     calls[callId].active = false;
+    calls[callId].playFuture.waitForFinished();
     if (calls[callId].audioOutput != nullptr)
     {
         delete calls[callId].audioOutput;
     }
+    calls[callId].audioBuffer.clear();
 }
 
 void Core::playCallAudio(int callId, ToxAv* toxav)
diff --git a/core.h b/core.h
index ed03a9837..2f48ecd16 100644
--- a/core.h
+++ b/core.h
@@ -89,6 +89,7 @@ public:
     int callId;
     int friendId;
     bool active;
+    QFuture<void> playFuture;
 };
 
 class Core : public QObject
diff --git a/friendlist.cpp b/friendlist.cpp
index 997372f8b..35da62f2a 100644
--- a/friendlist.cpp
+++ b/friendlist.cpp
@@ -6,6 +6,9 @@ QList<Friend*> FriendList::friendList;
 
 Friend* FriendList::addFriend(int friendId, QString userId)
 {
+    for (Friend* f : friendList)
+        if (f->friendId == friendId)
+            qWarning() << "FriendList::addFriend: friendId already taken";
     Friend* newfriend = new Friend(friendId, userId);
     friendList.append(newfriend);
     return newfriend;
diff --git a/main.cpp b/main.cpp
index 8e46d5bb2..261377207 100644
--- a/main.cpp
+++ b/main.cpp
@@ -33,3 +33,21 @@ int main(int argc, char *argv[])
  * An extra side panel for groupchats, like Venom does (?)
  *
  */
+
+/** NAMES :
+Botox
+Ricin
+Anthrax
+Sarin
+Cyanide
+Polonium
+Mercury
+Arsenic
+qTox
+plague
+Britney
+Nightshade
+Belladonna
+toxer
+GoyIM
+ */
diff --git a/widget/widget.cpp b/widget/widget.cpp
index 7f42c347a..4987b443c 100644
--- a/widget/widget.cpp
+++ b/widget/widget.cpp
@@ -383,6 +383,8 @@ void Widget::onFriendRequestReceived(const QString& userId, const QString& messa
 void Widget::removeFriend(int friendId)
 {
     Friend* f = FriendList::findFriend(friendId);
+    if (f->widget == activeFriendWidget)
+        activeFriendWidget = nullptr;
     FriendList::removeFriend(friendId);
     core->removeFriend(friendId);
     delete f;
@@ -449,6 +451,8 @@ void Widget::onGroupWidgetClicked(GroupWidget* widget)
 void Widget::removeGroup(int groupId)
 {
     Group* g = GroupList::findGroup(groupId);
+    if (g->widget == activeGroupWidget)
+        activeGroupWidget == nullptr;
     GroupList::removeGroup(groupId);
     core->removeGroup(groupId);
     delete g;