Are you using a quick tune drop away or standard quicktune?

If using a standard one, it sounds like a minor fletch contact problem either cause by improper nock rotation or form. Your arrow spine should be OK.

If using a drop away make sure you set it to stay up LONGER not drop quicker...biggest mistake people make setting up a single cam bow that has some nock travel (like the Pat does).

Also you are shooting@high speed. At those kind of speeds there is very littleto no margin for error in tuning, or shooting form with fixed blade heads.

Once I got a properly spined arrow in mine, fixed blades shot great for me at speeds approaching 290 FPS (assuming I did my part).