Sampled audio has crackling (even during monitoring)

Turned on my MPC3000LE (Vailixi 3.50 / 32MB) for the first time in a couple of years, and it sounds great, except that newly sampled audio has quiet but obvious crackling. Happens both on monitored audio during recording and on the resulting sample.

It is definitely in the box, as I have tried switching mixers.

Any ideas? Should I clean the RAM slots?

maybe your gain knob is dusty.. this happens on some of the other mpcs after a while... if it's the whole sound even loaded stuff then maybe it's the volume knob. There is contact cleaner spray like deoxit that you can spritz in to clean it.

Thanks for considering! Any sounds already in the box sound great; only new samples show the crackling.

I will clean the pots presently. That said, I have a good amount of hardware DIY experience, and this cracking doesn't sound like a physical connection issue to me. Feels more like a sampling system problem.

Could it be a RAM issue? I just cleaned the SIMMs and their slots, so connection isn't a problem.

When RAM goes bad, does it cause errors like this in sampling quality?

mr_debauch wrote:maybe your gain knob is dusty.. this happens on some of the other mpcs after a while... if it's the whole sound even loaded stuff then maybe it's the volume knob. There is contact cleaner spray like deoxit that you can spritz in to clean it.

yeah that is possible... except it doesn't explain the samples you are loading into ram working fine.... maybe there is a loose connection. that is another possibility. I would say try to disconnect and reconnect all connectors while you are poking around in the mpc.

I was assuming that live recording is much more taxing on RAM than playing back a pre-recording sample, but that's a great question.

I will disassemble, check connections, and deoxit liberally.

mr_debauch wrote:yeah that is possible... except it doesn't explain the samples you are loading into ram working fine.... maybe there is a loose connection. that is another possibility. I would say try to disconnect and reconnect all connectors while you are poking around in the mpc.

I would try turning the Record Level knob back and forth through it's full range about 20-30 times first, to see if that cleans it up at all, before disassembling it and spraying Deoxit anywhere.

Thanks for considering! That was my first move--didn't fix, and there didn't seem to be any relationship between knob and degree of crackling.

SimonInAustralia wrote:I would try turning the Record Level knob back and forth through it's full range about 20-30 times first, to see if that cleans it up at all, before disassembling it and spraying Deoxit anywhere.

agitprop wrote:Thanks for considering! That was my first move--didn't fix, and there didn't seem to be any relationship between knob and degree of crackling.

don't forget to check the record level switch on the backside of the mpc. when i received my mpc3k, that switch was in a "half-position" somewhere, so moved it a few times back and forth until it sat nicely in the three positions.

Great tip! Checked and switch isn't causing either.

Ordered new RAM, as it's cheap and might as well try replacing.

krishi wrote:

agitprop wrote:Thanks for considering! That was my first move--didn't fix, and there didn't seem to be any relationship between knob and degree of crackling.

don't forget to check the record level switch on the backside of the mpc. when i received my mpc3k, that switch was in a "half-position" somewhere, so moved it a few times back and forth until it sat nicely in the three positions.