E53 Radio issues

[gstan]

Hi all, i note many comments about factory fitted radio, but is there a definitive answer on how to fix it without installing aftermarket.
I have nav,tv (not digital, so useless). & widescreen.

Issue is, it has a mind of its own, sometimes no sound but orange light still on, no sound, no orange light, stays on after shut down but won't let you adjust volume or stations. Nav is not affected & still operates during these hissy fits. Pretty frustrating, but i am keen if possible to keep genuine system.