We have around 2 ft of ice. Seems like I can drill 6 holes easily, then for whatever reason, the auger won't bite when it gets down over a foot. Still has full power, just not cutting. Applying more pressure doesn't really help either. I have a Pro 4 lite, but noticed the same thing with my previous Legend Lightning. The blades aren't icing up. Anyone got some ideas on what I'm doing wrong? If the ice is under a foot thick, I've never had issues. Only the thick stuff.