My machine was running normally in "Fast Spin" mode when there was suddenly a loud bang followed by a loud thumping noise. I immediately shut it down, emptied it of all clothes and removed the top for closer inspection. I found nothing visibly out of place and decided to try starting it up again. It started in the fast spin cycle and seemed to be running smooth until high gear kicked in. Almost immediately after kicking in it shut down as though a breaker popped yet I could still hear the buzz of the timer. Also, during the brief time it was in high gear the thumping was present but only lightly. Any clues as to what I should be looking for?