High pitched whine after stereo install.

So I installed the aftermarket stereo this weekend. It included a head unit, 7 band EQ, 4 speakers, 4 channel speaker amp, single 12" sub, and monobloc sub amp. Everything is currently put back together and works fantastically, but there is now a high pitched whine coming from what sounds like somewhere behind me. During idle it stays at the same volume, and gets a higher pitch as I accelerate. Once the car shifts, the pitch of the noise drops accordingly. It never gets louder, the pitch only increases and decreases upon acceleration and deceleration. The noise itself is similar to when one takes a disposable camera and charges the flash. That sort of high pitched whine. Has any one else experienced this, understand what sound I'm talking about, or have any suggestions? I already double checked all the wiring and everything seems to be in place and correctly and snugly hooked up. Thanks guys, - Hollywood

You have a bad ground somewhere, or the wires are routed close to something that's interfering with the speaker. You need to either find that bad ground, or install a noise filter.....

Are you using inexpensive equipment? Some of the low-end brands skimp on noise filtering circuitry. Good brand name components tend to stay more quiet in my experience.

With the system on and engine running, try disconnecting RCAs to each component. You should be able to pinpoint the source of the noise this way.

I'm sure that Scott and Aaron know more than I do about how to fix it, but just FYI what you're hearing is the alternator...

You might need to add a very small capacitor on the alternator post to help filter the noise.