The bose system in my car has recently started buzzing when it is turned on. It does not play any CD audio or AM/FM radio. The CD player and tuner both appear to work, the track and station are displayed when they are on.

The buzzing is low frequency and it doesn't matter whether the engine is running or not.

I know I should probably just install an aftermarket head unit, but I'd really like to keep the car as original as possible.

Anybody know what this might be? Amplifier?

 

I had the same problem, and it was a bad battery.