I've noticed twice now, that my fairly new (only 2 months old) Dolphin Nautilus Plus has powered down before the 2.5 hour cleaning cycle was complete? Both times it was stuck on the steps where it powered off. Does it have an automatic shut off if it senses that it's stuck before it overheats? It's never did this before, wondering what could be wrong or if it's just suppose to do that? Not sure since it has gotten stuck before and just stayed on until I moved it. Anybody else have this happen?