Golf Mk5 GT TDI Acceleration Wobble

Hey guys. I've got a wobble under acceleration on my Mk5 Golf GT TDI. It's most noticable in 6th gear at about 1,700rpm. It's worse when going up hills. Strange thing is.....if I'm at 1,500rpm in 6th and I put my foot down slightly to accelerate.....when it gets to about 1,700rpm it will wobble. If I'm at 1,500rpm in 6th and I put my foot to the floor though, it just accelerates smoothly through 1,700rpm without wobbling?? :mad0259:

Any ideas would be hugely appreciated as it's driving me dull :thumbsup: