framing on picture print

[brifast]

I have the Canon MG8120. I was printing out photos and they were coming out just fine with borders then the next one was all out of proper form. The top and bottom borders were slightly bigger and at the end of the print there was white block which I believe cropped some of the picture. I kept on printing with the same result. I took a USB flash drive to the printer thinking it might be iphoto and the same result occurred. I assume it is the printer but have no idea what setting needs to be changed. The problem occurred in the middle of printing nothing was changed during that time.

BF