Speaker Problems

I just sold my 2000 S430 last week and the new owner called me with a problem he's having with the stereo, etc...
Of course, it all worked fine for years and now when I sell it, something goes wrong.... Anyway I'm hoping to help him out.
He says that the radio comes on, nav comes on, looks like it's all working, but no sound out of the speakers.
Anybody have any ideas?
Thanks so much,
Mike

well i can only assume that he did... but you never know, huh?
but raising/loweing the volume would take it out of mute mode, right?

is there a reset for the command?



