Vibration In Gearbox On Low Rpm

[ClutchBurndout-:(]

in the morning its a pain to drive my r33 gtst manual, because in order to keep clear of a large vibration through the gearbox i have to change from 1st to 2nd at around 3k rpm, otherwise i get this vibration through the gearbox, it happens with every other gear on lower rpm to, but 1st is just the hardest since its such a small ratio. it seems to get a bit better as the box warms up but not much.

has anyone else got this vibration? ive checked the gearbox mount bolts and there nice and tight, what else could it be? or is it simply that my gearbox is tired?

cheers