Hi guys, This is what is happening: 1. I call a contact from my contact list 2. After a while (sometimes right awa, sometimes after several minutes, even hours) the notification sound of some devices goes away. Like for example in viber the notification sound is sooooo quiet that you cannot easily hear it. The alarm for example is only vibrating and produces no sound 3. At the same time, all the sound volumes are maxed and when I receive a phone call, the phone is ringing (quietly) but it makes sound. The youtube for example is also working. The screen unlock and lock sound can also be heard. 4. If you go to Settings --> Sounds and vibration --> Ringtone and select a random ringtone, the "Unable to play during call" message pops up and you can do nothing. Please don't ask me if I am in DND mode, if the volumes are maxed and so on. The sound and phone profiles are fine. There is just a bug somewhere and no one can tell where... BTW, my Android version is 6.0.1 if it matters somehow.