My MPC 4000 sampler is not functioning right

every time I try to sample it will sample correctly but when I try to play the sample back on the pads or the soft play button it will crackle come out loud on one side of the channel or play both channels low is this software issue or hardware can't figure it out

You might want to check and see if your RAM is seated properly or is not defective. If it is not, then go to your global page, and underneath the tab "Memory", try and defragment the memory after you have sampled the sounds and see what happens. If this doesn't work, it could be a hardware related issue. I just had the same problem with mine and what was needed was a replacement of the onboard RAM (Not to be confused with the 'user-installable' RAM) and the actual souind generator also was defective as well , both of which are more processor related problems. MY 4000 works perfect now even at 96 Khz ! THis was the problem in my MPC, hopefully it is not that extreme in yours. TSI Repair did the whole thing for about $226.00. I hope this helps. Reub.