Been having some issues with my gerabox on 06 vectra. It's been difficult to change gear since I got it - kind of like the clutch isn't pressed all the way in when you change gear (which it is). this is partic noticeable going from 1-2 and 2-3. Took it back to the dealer just after I got it but they claimed it was fine and was like this because it was a cable system. He also said I had to let the rev's drop to below 2000 before shifting (no use if you're accelerating hard).
So - my question - does this sound like the shift cables need adjusting? It feels like it's crunching a bit when changing gear and doesn't just neatly slot into the gate!