[REFACTOR] inlined final field

The value contained in the class AudioSettings was only used in one
place. Inlined this value and deleted the class.

Change-Id: I631782ff319021ca23bc0b21df5d7f86825a86b9
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1136
Reviewed-by: Franz Zieris <zieris@inf.fu-berlin.de>
Tested-by: Jenkins CI