Rodeo Belt Problems....Help!

I have a 2003 Rodeo LS bought brand new and has 17000 miles on it. I love it, it's been great to drive and problem free except for a darn belt that squeals. I replaced it for the first time 4 months ago and I remember the weather had been especially rainey for a couple of weeks. Now again, it' been rainey for the past week and the belt started to screech again. I called the service dept and told him I have the same problem again, and the quy said "it's rainey lately, when it dries out it'll stop making noise". What a load of carp! I said "Oh, so I paid $26000.00 for a vehicle I can only use when the weather's dry....yea right, I'll be bringing it in tomorrow". Question: Anyone else with this belt squeaking problem? What can I say to the service people to make them fix this right and for the last time? Thanks.

There may be someting up with one of the pulleys, idler or tensioner. I know the serpentine belt setup can be a PITA with that (noise). I had a chevy truck that would chirp a bit all the time, no matter what I did. Be sure to stress to the dealer that this had been addressed before & they need to look deeper than just a new belt.
G/luck
Joel