Does anyone have suggestions for this electrical problem:

I have static and interference with my FM radio reception with the motor running, however, with the motor off... no interference. The interference sounds like static humm / squeal and becomes more pronounced with higher RPM. No interference with the iPod adapter or listening to CDs.

I have checked the sparkplugs to make sure the caps are on tight, checked to see if any of the sparkplug wires were bad, also checked all the connections in behind the stereo, and looked at the battery cables. I did notice damage to the starter cable (from the battery positive terminal to the starter). The cable was abraded by resting against the serpentine belt. I have attached a pict of the damage. Could it be a bad alternator?

I know one problem can be a loose ground connector / strap, but I don not know where they all are. ALLDATADIY didn't have a good component location diagram for all of the ground straps, does anyone know where all of the grounds are located.

Any ideas would be much appreciated because I'm moving from Nor Cal to San Antonio in a few weeks and having to listen to this static will drive me crazy. Cheers, Steve

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Sounds like alternator whine. One of your stereo components might need to be regrounded. The link sounds like a reasonable way to isolate your problem, though it sounds easier if you don't have many stereo components! (This isn't something I know much about, but it looks like the forum has plenty of audiophiles; I expect someone here has actual experience with this issue.)

 

Here is an update on what I have trouble shot with this issue:

Here are my symptoms:

1) I get the Sirius "Acquiring Signal" message on my radio with a clear sky view and the antenna is on the roof.
2) At idle I do not have any signal drop out.
3) At higher RPM I will get the signal drop out and "Acquiring Signal"
4) My normal FM reception will have a static like noise in the background and it increases intensity with RPM (my set up is direct into the receiver w/o FM modulator)
5) I did not have these problems for the first year of the install but after sitting idle for 4 months the problem has arisen and gotten worse.
6) No interference in CD play or iPod adapter play

Here is what I have trouble shot:

1) Removed and replugged in antenna from pioneer Sirius adapter
2) Read this article on signal noise
3) Listened to the engine compartment with the AM radio trick in above article - loudest static increase is in the vicinity of the alternator but there is static all over the engine compartment near the ignition too.
4) Looked for grounding / sparking ignition wires in a dark garage - didn't see any
5) Checked the voltage on the alternator it is 14+ in the car dash and with a volt meter 13.5 at the alternator and 13.0 at the battery terminal.
6) I have a new antenna thanks to Sirius's great customer support, I haven't plugged it in yet... but since the problem does not occur at idle I don't think it is a bad antenna.
7) Installed new battery cable to replace the one that was worn out in the picture.

Here is my set up:
02 Chevy Blazer 4x4 4.3L 4dr
Head receiver: Pioneer DEH-P7800MP
Sirius adapter: Pioneer SIR-PNR2 Sirius
iPod adapter: Pioneer CD-iB100ii
Purchased from Crutchfield w/ no other mods to the factory system. I'm grounded into the factory harness.

Thanks in advance for any and all help / advice. I'll post my results to this problem.