I'm aware that it may be a bug and that nightlies can have bugs like this.
Despite that, I have always flashed cyanogenmod roms on my phone since CM7.
There is no stable release at the moment on Z1. So, the nightly being buggy I got that. Not a problem.
My question was is it a bug or is my phone defective since no one seems to have this problem in any post on XDA.
Seems very strange that people would complain over display behaviour, sound too low, that kind of stuff but no one notices they have no sound in the clips they record with the camera.
Maybe have I made a mistake at some point, maybe it has to do with the unlocking of the bootloader ?