MPC3000 Headphone jack output makes high pitched noise

Sorry if this is a known issue...

I just bought a MPC 3k on ebay, problem is I'm getting a high pitched tone (hum) through my headphones. Actually there are 2 frequencies, one very loud the other one is quite dim and disappears as soon as I turn off the display. Obviously the louder one is really annoying.

The seller (we are both form Germany btw) couldn't help me either (of course) .

Additional Infos:
nothing attached, no other scsi devices, no card reader. plugged straight into the socket. MPC is in mint condition, only modification I know of is the internal 220V power supply, which according to the seller has been done in a professional synth repair shop. Headphones are ok too.

What are the chances to fix the headphone jack?

Thank you for helping me out.

sounds like you are experiencing 2 separate problems.

1 - The backlight inverter is old and has become noisy. These are difficult to source out, as NICHIA has stopped making the originals.
try AkaiJazzcat - he's on here.

here's his Facebook -
https://www.facebook.com/pages/Jazzcats-Akai-parts-repairs/367209503294538 he could probably build one for you.

2 - you have a grounding issue that is sending that noise out of your headphones.

this could be caused by a number of things. sometimes its a grounding issue caused by a loose screw on the bottom that connects the floppy disk drive. alternatively theres also a thread about this specific issue with directions on how to resolve it.
heres the thread. I did it and it worked for me.
http://www.mpc-forums.com/viewtopic.php?f=4&p=1218967

Thanks a lot viacom, good info!

I plugged my external scsi iomega drive to the unit which really helped to minimise the noise, even to a bearable degree.

But I'm going to try out the soldering trick. Is there anything specific I should look out for when buying a soldering iron/kit?

Do not do the soldering suggested by old gear guy. that is not a proper repair. If you decide to contact jazzcat, ask him, he willl be sure to let you know its a bad idea.

Like viacom said, the inverter noise and grounding buzz are two different things. Turn the backlight off. Fix the buzzing from the grounding first. then see how loud the inverter is by itself. If you really want it replaced Jazzcat or mr white have inverters.

C-Quence wrote:Do not do the soldering suggested by old gear guy. that is not a proper repair. If you decide to contact jazzcat, ask him, he willl be sure to let you know its a bad idea.

Like viacom said, the inverter noise and grounding buzz are two different things. Turn the backlight off. Fix the buzzing from the grounding first. then see how loud the inverter is by itself. If you really want it replaced Jazzcat or mr white have inverters.

ok thanks, from what I hear, the inverter noise is still thin and isn't bothering me too much, at lest not yet. And if it doesn't lead to other issues I'd want to fix the grounding buzz first, as you suggested. Still, I'm gonna contact jazzcat tomorrow and see if he can help.

But back to the grounding problem... isn't that that the noise is being taken care of by the soldering? If not soldering what else could I do? I already checked the screws underneath the FDD. Maybe I should check them again with a newer screw driver. Mine is worn out now and I was careful to not damage the screw head.

Is the SMPTE option installed in your MPC?