I just noticed today that there is a squeaking sound coming from my car when the A/C is turned on. When the car is moving I can't hear it (I don't know if it goes away or I just can't hear it over the elevated engine noise). Is this an indication that its time for a new belt? I be surprised since the belt I have on it is only about 2 yrs old (was put on along with the ASP underpulley). Ane ideas as to what it might be?