Problem with Static when Sampling?

lately, ive noticed really bad things going on with sounds that i sample.
there is a substantial amount of static underlying the sounds being fed into my mpc.
at first, i figured my audio cables were just old, so i replaced them.
the new ones, however, have not helped any.
this problem is persists while sampling different instruments and things, so its not the device im recording.

the biggest problem here is that when i was sampling drum sounds (which, obviously, are of the utmost importance) from my mbox, there was a high pitched buzzing behind the samples.
it was really faint, but once i amplified the sound at all with normalize or reverb, it was an even larger problem.

this happens even with my rec gain all the way down.
i also took out the audio cables and turned the rec gain all the way up to see what the result was, and it was a horrifying fanfare of static.

is this supposed to happen?
shouldnt my mpc be silent when nothing is plugged into the rec ins?

i just want to record my drums the way they should sound

It could be ambient electromagnatism. Is your MPC sitting next to any other equipment? What else is plugged in near the MPC?

For example, when my cell phone rings, I hear a strange blipping noise just before the phone rings, from the headphones plugged into the MPC. Apparently whatever signal is being sent by the phone effects the MPC. If my cellphone can effect the MPC, then maybe a fan on a nearby PC is causing problems, or some equipment is causing noise through the power line, etc.

Is the MPC connected to absolutely nothing but headphones when you try this test? Any connections to external gear could potentially be causing a ground loop which would cause the problems you are describing. If it still does it with only the phones connected, you either have the problem Rex is describing or a faulty MPC.

BTW the mbox has s/pdif correct? Does it do the same thing through the digital input?

i have this one particular mouse that when plugged in to my laptop makes a weird noise occur in the mixer, which gets picked up by my MPC or whatever device is 'listening' to the main mix. the fix is simply using a different mouse.

there are numerous reasons you could get extra noise in the MPC. try moving the MPC to a new location, plugging it into a new outlet, while using only headphones for testing. try disconnecting various pieces of equipment to locate any troublesome devices. don't be afraid to check EVERY item attached to your setup.....

alright so i tried some of your ideas and heres what ive noticed:

when my keyboards are plugged directly into the record ins of the mpc,
the static and background noise is minimal
or at least low enough that it doesnt bother me.
even after normalizing them, the samples dont have excess static.

when i plug the mbox directly into the record ins, there is a persistent buzz and high pitched noise in the background.
the noises are barely noticable until the sample is normalized,
and then they become unbearable.

i also noticed while pulling the cables out of my mbox's monitor outs that i was picking up radio frequency through the cable.
when it was halfway out, i could hear music playing into my mpc.

elektrik, can you explain how to test the digital signal?
ive never used the s/pdif ports and realize that doing so just creates harsh static-type noises instead of the actual sound coming from the mbox.

thanks for your help everyone
rather than

It sounds like you have a ground loop problem between the computer and MPC. This is common. One thing to try is to use a 3 to 2 prong adapter on the computer's AC power plug to lift the ground lug. This cheap solution will often work wonders. You could also use an audio isolation transformer/direct box between the computer and MPC, but good ones usually cost a bit....

As far as the s/pdif goes, you should be able to hook up the mbox s/pdif out to the MPC s/pdif in and select the digital input on the MPC, but you may have to do some setup on the computer end -- check the docs for the mbox and the audio software for that as I'm not familiar with what you are running. The problems you are describing with it right now might be due to the ground loop, so it may not work until that's dealt with first.