Belt squeals even after replacement
 

I have a 2002 Mazda 626 4 Cylinder that I changed the belts on at the beginning of the year. The belts started squealing again so I had them tightened, but the squeal remains. Below is a list of symptoms the car is experiencing right now:

1. Belt squeals when the vehicle is turned on, sometimes even if the A/C is off when I start the car. Typically the noise stops after the A/C is turned off. I can turn the A/C on after the car has run a while without a squeal.
2. When the A/C is turned on while in drive, you can feel that it is putting a strain on the car.
3. I had a mechanic raise my idle rpm to 1000 to fix the squeal. That worked 2 days.
4. If the car is parked and in idle, the A/C compressor turns on and off every few seconds.

I think the fix would be to replace the A/C compressor; however I am not entirely sure that will fix the squeal. Anyone ever experience anything like this or have any suggestions. I hope I have been thorough enough.