You didn't get me.

If you set up the signal slot connection whenever you START playing the sounddata on an Audiodevice there will be multiple signal-slot-connections, if you play the same sound multiple times and you don't remove the connection with QObject::disconnect after play back stopped.

If you set it up only once when you create the sound everything is fine.

Callback: No need to ask. Just try what works. You can't break anything.

Good luck with your project!

Johannes