My 2000 A6 has the Bose option. About once a month, while driving, the power is lost to the radio. It turns off and when I turn the power back on it is in safe mode.

Since both the power and the standby memory power are apparently involved I need some suggestions as to where I should be looking for a problem.

 

Thats more than likely an issue with the radio itself and not the power into it. Its usually a sign that its overheating.

 

my 99 audi battire died and radio comes on safe mode

 

Here, my car is running, and the power goes out to the radio. It restarts in Safe Mode.