How to fix intermittent brake light issues in an Audi 80?

I've noticed that the brake lights in my Audi 80 sometimes stop working, even though the bulbs are fine. How can I troubleshoot and fix this issue?

Check the brake light switch, which can sometimes malfunction and cause intermittent issues. Be sure to also inspect the wiring and connections for any damage or corrosion.

Another possible reason for the issue could be a faulty signal relay. You may need to replace this component to resolve the problem.

It's also possible that there is an issue with the brake light control module. Have a mechanic check this and potentially replace it if necessary.