???Sound Only Coming Out of Left Side???

On my 2002 Toyota Tacoma PreRunner SR5, i have the factory installed radio (http://media.photobucket.com/image/toyota stereo/Mike92LX/1233253832.jpg). The problem is whenever i play cassettes, only the left side plays (i use a cassette-to-3.5mm for my ipod http://ecx.images-amazon.com/images/I/41WCTD6NX5L._SL500_.jpg).

I've checked the balance, tried multiple cassettes, made sure the wires were in all of the way, checked the fuses, and they're all functional. The CD player and FM/AM radio work fine.

What happened was that i was listening to the cassette while driving and all of sudden the whole right side started blaring static. After about a month, the static just stopped and now no audio even comes out. So what's the problem?

 

Welcome to TW Cody... You've done a good job trouble shooting and it seems to me you've narrowed it down to the cassette head especially if you've tried multiple cassettes and they do the same as your 3.5mm/cassette adaptor. Now whether that means the head is dirty, misaligned, or a wire failed is anybody's guess. I'd start with a cotton swab with some denatured alcohol on it and flip the cassette door open and swab the head with it until the head is clean. If that doesn't do it... it might be time to invest in an aftermarket CD with an aux out or iPod connection. You can get some nice ones pretty cheap. Good luck!