No sound from EVERY output. Just hum. PLEASE HELP, GIG SOON!

Every single output, analog outs 1,2,3, and 4, digital out, stereo out, and my headphones only release a low hum. All were tested directly to my speakers, headphones, and mixer, none of which are the problem. The record in only receives a signal when the main volume knob is at a specific spot (very low) and at that position I hear some sound but it is distorted and inaudible. Pad to internal sound is on. I have auditioned many sounds on my HD, my CF card, record ins from my turntable, and various synths, in all cases the mpc acts the same. No sound is outputed except a quiet distorted signal when the main volume knob is at a certain point. This suddenly happened for no specific reason. The ram is 128mb and every board inside is new while running jjos1 4.99. Fat pads and the pad upgrade is installed as well. It is the model with the black faceplate. I've read the manual 10 times over and googled it too death but can not find an answer. The voice monitor shows I have sound playing but I hear nothing but a low hum on every output. There has been no issues prior and at the time the sound cut out I was adding hats to a new beat. Nothing from the HD, CF, (internal is empty and has been) and beats I've finished are audible, only a hum. Everything is on stereo out so I should hear it. Please Help I have a live gig this coming Saturday as well as multiple beats I've not been able to work on

UPDATE. I replace my main volume and rec gain pieces and it still does NOT work. Has anyone has this happen to them??? Please Help!

What do you mean you by replacing the main volume and rec gain pieces? Did you de-solder them and solder in new pots directly to the circuit board? If so, have you performed any other soldering jobs to the internal boards?

Have you run any of the usual tests we recommend, just to rule out easily fixable stuff, like reboot with ERASE held down to reset the OS, taking out the RAM expansion to rule out bad ram, checking internal cables to ensure everything is attached to the main board correctly? Can you think of anything you did or changed before this happened, however insignificant?

Obviously it could be that the boards that deal with audio output are faulty, but as there are separate boards for the 6 outs and the headphones so it's maybe something on the main board that is causing the problem - either way these are costly components and if it is this it might be cheaper to just get a new (s/h) MPC1000 and sell this one for parts. Hopefully one of the regular electronic whizzes can offer something more concrete, or you might need to take it to a service centre.

This happened to me once OP. I fixed it by re-seating the RAM in the DIMM slots underneath the back cover.

This kind of issue is often caused by a failed or failing power supply. I'd recommend first checking all the voltages with a multimeter, and ideally also look at the power rails with an oscilloscope. If you're not experienced in testing equipment withe the covers off while it is turned on, it is probably better to get a pro to repair it for you.

Hum and partial/non functionality in older gear is usually due to a dead electrolytic capacitor and/or a dead regulator IC or associated pass transistor. This is actually the cause of a large proportion of failures in older gear. Again, if you don't know what this means, ask for help from a pro!

I have exactly the same problem,did u find a way to fix the problem.