This may not actually have anything to do directly with OCS but I'm asking for help if you can anyway.
Just lately during flights, the co-pilot and ATC voices sound ok to start with but then, about threequarters through the flight the voices get very faint and in the end I have to read the instructions and replies.
Strangely, when I've landed. the sound level of the voice giving me directions to parking is fine.
Has anyone any idea what could be the problem and more to the point, how to overcome it please?