Hmmmm I bet you mean fps. (feet per second)

Anyway Muzzy is a tried and true broadhead that seems to fly very well I have a feeling that your problem is not the broadhead.
If you have a friend you can borrow a different broadhead from for a couple of test shots this would let you know if its the broadhead or your setup. Just make sure they are the same weight and spin test them to make sure they are true.

I' m sure there is someone here thats more qualified to help you, maybe someone else will chime in...