Sony AVD-K800P...Distorted sound..... barely audible

[PDXsony]

OK.. I got this thing on clearance I thought it was just scratched and missing speaker wires and remote. But when I got it home I found out that it was barely audible and distorted. I opened it up and saw that whoever manufactured this thing had dripped solder all over the inside even across a couple of circuits. i cleaned them up the best i could. Then I put it back together. It is louder and not is distorted but it is still REALLY bad. the dvd player still plays but no sound...maybe little... I am trying to obtain schematics for this. I know I can buy them I am just hoping to find them at no cost. Anyone with a tip on that I would really appreciate it. Anyone with some advice AT ALL I would REALLY appreciate it.