I recently replaced the clutch in my 2006 RX-8. When the engine RPM gets to about 7500 RPM the clutch disengages by itself. Not just slipping but rather a full disengagement. If I lightly tap on the clutch pedal it will go straight to the floor. I can change gears and the pedal will pop back out on its own at just below 6000 RPM. When the clutch disengages I can change gears even without touching the pedal or rev matching.

The clutch was brand name and I have used them prior. Could it be an issue with the pressure plat? I have not seen this before. Any ideas? Thanks for your help.