As far as the saw goes there could be several problems. I would imagine if this started from day one the tube is either clogged, pinched or not connected properly. Also the speed you run your saw will effect how hard the blower will blow(not sure if you knew that or not). I would just go for it and try to fix it. It really should not be too hard.
as far as the Bits go........Dan said it best!
Good luck