Was yours a creaking sound that happened every tire rotation? That seems to be what's happening when I'm driving for a distance anytime it's in the mid to upper 90s. It used to only do it when I was in gear and there was tension on the belt, then last week it would creak when I was coasting out of gear.
Belt is getting too tight as it warms up excessively and is over-stressing the pulley bearings. Need to take to the shop and have the belt tension reset. Fixed my problem 100%.