There is a LED on the microphone next to the SOS button on the roof. When you start the car its red then turns green. It buzzes upon start up then fades away but lately it's been buzzing longer and longer. Its very high pitched, unlike anything I've heard in any bmw. For a while it was a short buzz at startup now its Up to ten minutes after startup or longer Any thoughts?
Forgot to add that previous owner installed a built in valentine with remote speaker installed next to EDC button. Car also has laser jammers with no controls that I know of.
Red at start up then turns green.
Here's another pic. Just drove 20 minutes to work buzzing the whole way.
Thought it was factory because the install is perfect. Looked at an 06 m5 yesterday. No light.
Forgot to add that previous owner installed a built in valentine with remote speaker installed next to EDC button. Car also has laser jammers with no controls that I know of.
Red at start up then turns green.

Here's another pic. Just drove 20 minutes to work buzzing the whole way.

Thought it was factory because the install is perfect. Looked at an 06 m5 yesterday. No light.