Missing sound during call when using bluetoooth devices

REPRODUCIBILITY (% or how often): 100
BUILD ID = OS VERSION (Settings > About product): 4.3.0.12
HARDWARE (XA2, X10, X10 II, …): X10 II
UI LANGUAGE: polish
REGRESSION: (compared to previous public release: Yes, No, ?): yes

DESCRIPTION:

The problem occurs only when using bluetooth devices, tested with bose soundlink revolve plus 2, jabra motion uc ms, jabra elite active 75t. The microphone works - call reciever can hear me correctly, while I do not hear anything in all cases. Moreover there is no recall option and bluetooth icon not visible during connection of the device. Additional fuctionality does not work either, cannot answer or reject call using device buttons

PRECONDITIONS:

STEPS TO REPRODUCE:

  1. Connect Bluetooth device
  2. Start phone call via connected device

EXPECTED RESULT:

ACTUAL RESULT:

ADDITIONAL INFORMATION:

(Please ALWAYS attach relevant data such as logs, screenshots, etc…)

Can you check if the volume is high enough? Press the volume up button during the call.

Thank you for tip. The sound appears at 50 % of volume bar. Nevertheless the fuctional keys on any Bluetooth device still do not work