I have an M6 z28 and the tranny seems to be having some problems, sometimes the when I put the car in reverse and let go of the clutch it is not in reverse but the gears will grind if I try to push it into gear further, but then when I switch it back out it usually works the second time....and then for the first time the other day I was reversing and it fel out of gear it seems that I have some sort of problem but I'm not too knowleged about tranny's

Will someone please help me and figure out wut the problem is ?

thankyou