How to fix a faulty audio system in an Audi A4?

My Audi A4's audio system suddenly stopped working and I can't figure out why. I've checked the fuse and all connections, but everything seems to be in order. Any ideas on how to fix this issue?

First, check if there are any error codes displayed on your dashboard. If so, refer to your owner's manual for the meaning and troubleshooting steps. If not, try resetting the audio system by disconnecting the car battery for a few minutes. This usually solves minor issues.

Another possible cause could be a faulty amplifier. Try swapping it out with a known working one or take it to a professional for testing. It's also worth checking if the audio system is properly grounded.