what kind of mic do you have? Bluetooth headset with integrated mics have 2 different "sound qualities", a high quality for only the headphones, and a very lower quality one when you use the mic. the headset will change to the lower "communication quality" once the mic is engaged downgrading the general audio. Could this or something similar be what's happening to you?
this is not a deadlock bug, this is the way bluetooth mic work.