[s-cars] Noisy serpentine belt

[JR]

My serpentine belt has just over 5K on it and it's squealing like a 
stuck pig already.  Why does this happen?  What should I do about it?  
Spray on belt dressing renders it silent for about 20 minutes and then 
it's back to squealing away.  What can I do to prevent this from 
happening so fast next time I replace it?  Is there a better belt or do 
I need to adjust it somehow?

Thanks,

JR