"Squeel" Problem in 1999 V6 5 spd

Ok heres the deal...1999 Mustang V6 5 spd. The problem is that the car will "squeel" at low speeds and in 1-3 gear. The problem is it does not do it all the time. It is very inconsistant. To me it sounds like something maybe in the clutch/flywheel area? I know its a long shot, but has anyone ever had or heard of a problem like this? It will not do it over 40 mph or in 4th gear. And as I said, it does not do it all the time, only certain times. I thought maybe a throwout bearing, but if it was that wouldnt it do it all the time? The car has 89k miles and has never had any tranny/clutch problems before. Thanks:SNSign:

I guess I should add it also sounds like a slight vibration of something metal maybe....at 25 mph in 2nd gear it was doing it, I pushed the clutch in and it still did it, I then put the car in nutrel while holding the clutch and it did it, then I let it in nutreal and let off the clutch and it still did it...dunno if that helps?