Need audio help ... whistling noise when radio is on
 

Not sure what happened. I think it is my amp causing it. A very high pitch, annoying whistle when I turn my radio on. Even if I turn the volume off, the whistle is there. Higher revs, louder whistle. Power the radio off and the whistle is gone.

Any suggestions?

Does the pitch go up too when you rev higher? If so, it's an alternator whirr. I had it on my rx8 every once and awhile. Your player needs a better ground basically. Either that or two wires are touching that shouldn't be. Sorry I can't be of more help.

I get that same problem, kind of sounds like a jet spooling up as I rev

Just like jordan said, u need to makr sure you have a secure clean ground and make sure u dont have a bare power cable touching a bare negative cabe

If the amp power source and rca are wired from the same side its definitely ur problem.
Try to pass the rca cables on the other side

Ground loop somewhere in the car. Very common issue with car audio systems. try re-grounding the radio, antenna, amp, and battery to the chassis. also check your alternator ground and see where it goes. typically, the alternator case will ground through the block and then you'll have a good size ground cable running from the block to the chassis/battery.
on a 20 yr old car, any or all of those connections could be corroded or missing.

If cleaning up the grounds doesn't solve it, audio shops sell ground loop isolators for about $35 (last time I looked 10 years ago), that just plug inline with your RCAs between your head unit and amp. Don't buy a $10 cheap one- I went through about 5 different 'discount' brands that never worked. Finally broke down and bought one from a name brand audio supplier, and problem solved.

It was a ground issue. Thanks!