Hello, I have an 86 firebird with the factory radio and performance sound option. I listen to cassettes and lately I have noticed that they are becoming increasingly muffled and some squeak pretty bad when being played. The squeal is audible with the volume down and is apparently causing enough interference to play through the speakers too. The deck plays at the correct speed. I cleaned the head manually and that did nothing. The cassettes play fine in all my other tape decks, so I'm thinking that the tape head is worn out. Any input? Thanks in advance

 

Try running a "wet" head cleaner cassette in both directions. There is a "dry" type that you can just stick in the deck and play,... or a 'wet style that you apply cleaner ( or isopropyl alcohol ) to the cassette before playing it. Let it play in both directions. Another maintenance task is to play a cassette de-magnetizer - but when you use one of those cassettes you play it from the beginning ( or rewind it to the beginning first,.....) & only allow it to play in one direction. ( Be sure to turn the volume down to ZERO before playing it !) If you allow it to play the other direction it could re-magnetize the head.

If you attempt to maintain the cassette deck using these 2 types of cassettes ( "wet" head cleaner and de-magnetizer ) and there is no improvement than the cassette mechanism needs repair or or simply replaced.

 

I cleaned the head and other moving parts with some isopropyl acohol, and it seems to have done the trick. Thank you for your input.