Sound during phone calls 10 V

REPRODUCIBILITY: 100% (always)
OSVERSION: 4.6.0.15
HARDWARE: Sony Xperia 10 V - xqdc54 - xqdc54 - 1.0.0.25 - aarch64
UI LANGUAGE: Dansk (user: da_DK, os: da_DK.utf8)
REGRESSION: no

DESCRIPTION:

Turn the Volume up and down is not working.

PRECONDITIONS:

STEPS TO REPRODUCE:

  1. Make a phone call
  2. Turn the volume up and down

EXPECTED RESULTS:

It is not possible to turn the sound up and down. Only the minimum sound works.

ACTUAL RESULTS:

Only max. sound

Device Owner User: defaultuser
Home Encryption: enabled

the initial version of this bug report was created using Bugger 0.9.10+git5