Originally Posted by skillz335
I really appreciate your help. after researching what you said, and if i understand correctly,. I wouldn't know where to locate or isolate any bad soldering, but would trying to clean the board with isopropyl alcoho help? I already tried compressed air. also if with the alcohol would I just need to clean in the general area of the faders or should I just go over everything on the circuit board?
No. I was thinking there may be a connector linking sections of the mixer together. There could be a poor or 'noisy' connection carrying the signals used for the troublesome circuit. Sometimes a connector or pin will get tarnished and cause what's known as a high impedance connection. Sometimes just unplugging and re-plugging the connector will clean the connection by the scrubbing action of the two surfaces, the pin and the socket will clean themselves. You have to exercise great caution though as most of these circuits are static sensitive and you could zap a chip without knowing it and be in worse shape than what you started with. I wouldn't go cleaning the faders with alcohol as they have motors and grease/lube for both the track and the movement and the alcohol could dry out the bearings. Also, if you've already blown it out, I don't think you have a dirt problem.
My best advice at this time would be to get it in front of someone that knows about the device and has a schematic. It most likely has a lot of surface mount components and they take a different set of skills to repair than the older through hole componentry.