Why am I hearing a squeaking sound at start-up from the compressor? on 1995 Chevrolet Suburban 1500

Start up truck and I hear a squeaking noise from the engine compartment. When truck reaches operating temp. the squeaking stops. While squeaking when driving; as I come to a stop the squeaking stops, but when accelerating it comes back, but leaves when reaches operating temp.

Asked by for the 1995 Chevrolet Suburban 1500
Replace drive belt and belt tensioner!