if you are sewing two layers of normal weight, not stretch, cotton or cotton blend, this should not be happening. I'd check to make sure your foot is lined up square with the dogs, and that you are using a NARROW foot, not a wider zigzag foot that may give you a 1/4" gap, but does not line up correctly with the dogs.
Also check the bottom of the foot and make sure it's smooth so not catching the top fabric in any way. Then try adjusting your foot pressure and see if that works.
though with my last quilt, I had one cotton fabric that was lighter weight, and had a lot more "give" to it. it didn't feed at a different rate, but wanted to stretch as it was sewn, so I had to be careful with that one.