Radio/ tape player problems in 94 JGCL

[Gamer 101]

Ok to start off my dads JGCL's radio was acting wierd for a long time. When you first started it up on a clod day the radio would try to turn on the tape player but then it would switch back to the radio. We were able to fix that problem but i created another. As we were puting the radio back in i accidently touched to ground wire to the back of the case while the key was on. We saw smoke but after i turned off the key and put it back in it stil worked fine, but the tape player keeps spiting out a tape evertime you put one in. I tried to fix it myself but i must have made it worse. now the display dims and when you hit a big bump it makes a poping and static noise from the speakers. What can i do to fix it?(besides buy a new one)