small hum from my 8-outs

I got a smooth working 60 with the 2.12 running. The only problem i experience is when im tracking with the 8 outs. Some of the outs has sort of a humming noise going on. It really makes the mixing a nightmare. No problems with the stereo out though. Anyone experienced the same? It might be a grounding problem, but im not an expert in that field.

Also, one more thing/funfact; one thing that has been buggin me since I bought the mpc 5 years ago, it has the scsi option installed. Just a tease or what?

any tips would be very helpful.
Thanks in advance

anyone?

Oh I'll just take a swipe- sounds like you might have an internal issue that needs a pro tech.

Have you tried:
1. Using a ground lift
2. Using a power conditioner such as those made by Furman or Monster ?

While the noise is present- do you try doing everything possible- unplugging the main outputs, MIDI cables- SCSI- every possible thing in the name of trouble shooting?