High pitch whine

My '86 GT has developed a faint high pitch whine within the last few days which appears to be speed related.

I don't think it's the engine itself because I don't hear it when the car is stationary no matter what the RPM is. However, once I get up to 20kph(?), I start to hear a very high pitch whine that gets higher (but not necessarily louder) as the car speeds up.

It's not very loud, and I don't hear any growling or rumbling.

I can't really tell what direction it's coming from. I couldn't say if it's coming from the front or the back, left side or right side.

It almost sounds like tire tread whine, but I don't understand why it would've started it all of a sudden.

Suggestions?

Brake pads? Worth checking.

Seized wheel bearings? I know they’re not "seized" (as I was on the freeway today), but worth checking nevertheless.

Sticky e-brakes? I’ve never used the e-brake on this car, so that one is ruled out.

Bad ground on the radio? The radio is currently out of the car. Another one ruled out.

Rusty/sticky speedo cable? Is there actually a speedo cable in a Fiero? (Been awhile since I’ve had a Fiero instrument cluster out.)

Piece of engine insulation/(something) that has detached as is rubbing up against the tires? I’ll check the splash-guards in the wheel wells.

Try to isolate where it's coming from. Put down your drivers window and see if it gets louder. Then put it back up. Put down the passenger window and see if it gets louder, etc. Because the whine is so faint, it’s very difficult to hear with a window down due to the wind noise, but I’ll certainly give it a try.

Have a friend stand on the road as you drive past, maybe he/she could tell. I guess that’s better than my idea of strapping someone to the bottom of the car while I’m driving.

Anyways that's a couple ideas. There’s some good stuff there. Thanks Matt!

Yeah My Grand Prix Has A Small Whine As Well ...Ooo Wait Thats The supercharger ;)

Gd Lucking Finding The Noise ..Im sure When I Uncover Mine Next Spring I Will Have Some Odd Noises As Well