1998 Infiniti I30 Brake lights turn on by themself while pa

Brakes problem
1998 Infiniti I30 4 cyl Two Wheel Drive Automatic

Hi, I have an interesting issue my brake lights were staying on after I parked. My mechanic said there was a plastic piece that broke it was like a spacer but we couldn't figure out the true part name or find one he did whatever and replaced it. Months later I have a little different issue in that the brake lights come on but I can tap them while in park and the lights will go off, but I stand and wait and they will turn back on by themself. What do I do is this something I can deal with or better to take to a mechanic? Is it a fuse all test good inside and under the hood. I can not find the actual brak switch didn't get a book when I purchased the car used. Oh 6 years ago. Car has been great until this wierd problem. Oh the radio doesn't work all the time and the inside clock doesn't always light up or keep time not sure if this is an electrical relation the the above brake light issue.