oops i have an sti

i've been driving my v5 type r for a couple of weeks now and having much fun, although the dccd is catching me out on occasions.
it seems to drive sweet as a nut until i'm cruising in 5th gear and on light acceleration it jumps out of mesh.
all other gears are perfect and have no struggles into 5th, just jumping out.
could the engine mounts be worn and pulling out of gear?
i'd understand 1st and 2nd gear wear but this seems strange!

cheers

TonyBurns

iTrader: (3)

Get your gearbox to a subaru speciallist asap, it was a common fault that the nut for 5th gear wasnt torqued correctly at the factory, if you keep running it it will probably cost you a new box!

Tony

Splitpin

As above this is a very well known problem. In the worst case scenario it shouldn't cost you an entire box, but can easily run to a new synchro hub/collar/cones if you don't address it quickly.

In the best case, a new input shaft locknut, gear oil and three hours or so labour and it'll be fine.

mervil

iTrader: (5)

As said get it looked at asap, the box on my MY00 Turbo started doing it, didn't know what it was and seized all of a sudden

oops i have an sti

cheers guys
garage i bought it from gave me 28 day engine and gear box warranty on 07/09/10. but it's just been imported and the garage isn't a scooby specialist.
even though i might take a hit i just don't trust them with either!
trying to get a good local specialist... west yorks?
Uddersfield