I asked Colin this question also & he suggested printing from the SD card also, but thinks it might be the P/S as he has seen this similar problem before. Printing from the SD card 1st sounds like a good idea as it will rule out whether it is the USB connection on the arduino. I do not think it is a problem with the USB on my computer as I was having the same problem with octoprint, so I switched back to pronterface to see if that had the same problem. Also Colin said if I change to the DRV825 drivers, I just need to double the steps for each axis in the firmware that I change the driver on.

Thanks for the suggestions.