Humming Noise When Revving/Accelerating

[Si-Man00]

Can anyone help me on this? It's in my sister's 00' Civic Si, I didn't know where else to ask since this may be a "general" question. She's got 2 kicker subs and a pyramid amp with the factory deck. Everytime the engine is revved or just accelerating I get a "kazoo" noise through the speakers. Could it be that the amp/subs aren't grounded properly? Oh yeah the guys at the store had to install a switch to turn off the amp. Just thought I'd let you guys know every detail so i can get this problem fixed. I had to drive her car for a bit and it's really annoying, I just turn the volume up so the music drowns it out.
Thanks

[Impulse]

They installed a switch?? What a bunch of morons! All amps in the universe, including pyramid (ick!) have a remote turn on which is controlled either by the radio's power antenna wire or any switched 12V source. But on to your buzzing problem...

The buzzing is most likely caused by a bad ground connection. Check where the amp is grounded to the body of the car and make sure there is bare metal where the cable is connected. Another cause is that the power cable for the amp is running right next to any signal cables from the head unit. Make sure to keep you power cables as far as possible from the signal cables.

[rikig]

I had the same problem, and they checked the ground at said it was okay. They eventually just connected an RCA filter to the amp, and that got rid of it.