I started to have problems then treated myself to a new cutting mat AND a 60mm Olfa cutter, no problems at all now. I would really recommend investing in the 60mm if you do a lot of cutting, which I do.
I don't seem to have a problem with my rotary blades, and I have cut loads of fabric without changing the blades. Have you checked to see if the blades are put in backwards? That can make a big difference. It's worth a try. Hope you have better luck.
Do blades have a front and back? How can you tell?