1994 Pontiac Sunbird stereo lights flicker

While I brake, the lights in my factory stereo system flicker and dim... Could this be attributed to a faulty ground somewhere? The person who had the car before me was some 50 yr old lady who apparently tried to install foglights herself too, with a 10 amp fuse, so..... maybe she messed with it.  Any ideas on how to fix this??

First I'd ensure all your external lighting works as it should, for obvious safety reasons.  Either way, it sounds like it has something to do with the dimmer circuit.  Do your gauge lights dim as well?  I'd probably just install an aftermarket deck and not use the dimmer/illumination wires.  You may just try to cut these wires out of the harness, and isolate them with tape or crimp caps- at least until you can do some probing around with a multimeter.My ex once told me I have a perfect face for radio.