Blazer Forum - Chevy Blazer Forums - whining sound from radio

Well, electrical problems are my least favorite to diagnose and GM vehicles can be loaded with them. I noticed a whining noise that sounded like it was a bad in line noise arrester somewhere in the radio circuit. Not wanting to take apart my interior just yet I ignored it. It would increase and decrease in accordance with my RPM's. Well, I had a problem recently when I went to start the car it would turn over great but would not RUN. Never happened before, it's a 2000 4wd, but it just would not run. So, I had my wife turn over the ignition while I played with the pos. battery wire a little. Cranked right up... So, we drove it around an hour to do some errands and then we get back home, let it cool off a bit and I took the battery out to see if I could locate a fault connection. Well, I traced the positive wires down below the battery tray, then removed the battery tray to access them further, and located a junction box that housed a connection for the battery and 2 red connections coming out the other post on the other side 1 in = 2 out... Well, all I did was take it apart, remove the supply connection and cleaned it a little, no real sign of any corrosion or looseness. I then placed it back and had my wife finish up reinstalling the tray and battery. We did not tighten or loosen anything else in the starting or charging circuit, and I didn't go anywhere NEAR the wires for the radio. However, it started up fine and I noticed today that the whine that was coming from the radio is GONE??? Just curious if anyone has had similar issues and what their resolutions may have been. Also, does anyone have an idea of what we "FIXED"???

Thanks