Is it normal to hear a sqeak from the Flatline every time I take a shot? I don't think my Flaline is flowing properly, the gun does not rapidfire any more; no matter what psi I set it to. I have a Minimag w/X-Valve. I can't shoot more than two or three shots in a row. It keeps "chuffing", not fully cycling. I've tried different springs and carriers with no luck.