hello
on my audio 20, if the balance and fader are positioned on 0, only the left side of the speakers are working
if it is balance 4+ then all the speakers are working.
the central speaker on the dash is not working at all, I removed it and tested somewhere else and it seems ok.
do you thing it is a wiring problem, maybe someone before change something ?
it had installed a parrot telephone system and maybe they didnt install it properly?

I would like to be sure what to find before removing it and checking, if it will be a audio 20 problem then I will try to replace it, maybe with a newer version.