@Wizcrafts I had to read the OP a few times to get through my head what was happening here, and to see if it might be the motor as you pointed out in another thread.
Not being much of an expert on adjusting machines, I get myself in trouble now and then. I was helping someone with a domestic machine making an adjustment to the feed dogs, and suddenly they were feeding backwards. Finally got them heading the right way again but seemed to have really short stitches. Later I tried to help with the machine again as it now wouldn't feed at all. One of the clamps on the linkage that drives the feed dogs had cracked on the opposite side to the screw, so would not keep any adjustment. So being an older Brother domestic, it went in the garbage.
Anyhow, my take on this would be the feed dogs are misadjusted since it happens when hand wheeled and by motor.