Ok so recently purchased a spec 6 puk from td, got it fitted over the weekend an all seemed well, biting point was half to three quarters up the pedAl, smooth gear changes no crunching, happy chappy, then after driving for about 100 miles noticed that occasionly when pulling off in 1st, the biting point will drop right to the floor, an send me juddering off, and same into second, but then is fine through the rest of the gears, it probably does it like 1 in 5 times of trying too pull off, any ideas what it could be ? I thought maybe air in the system but it hasnt been disconnected so dont know