"Lurching" on power on or off
 

NOT a clutch problem, but feels odd.

When going on the power, the car body "wobbles" or "lurches" back and forward 2 - 3 times and similarly when lifting off the power, "lurches" forward and back a couple of times. There is no knocking or banging from under the car ( apart from hard launches at Scooby Shootout where it DID bang a lot under the car ! ).

Feels like some play some where between body and suspension, or engine/transmission moving, on power on / power off?

Already has STi IV dampers and springs with STi top mounts, Whiteline uprated front and rear anti-roll bars with PU bushes and metal drop links, uprated STi engine and gearbox mounts and new engine pitch bar, Full PU bush kit at front and Whiteline antilift kit, Powerstation bump steer mod, full 4 wheel alignment etc.

Any ideas? It drives fine normally, but is not smooth when lifting off / powering on for a second while it "lurches".

Have been told some rear axle link bushes are getting worn / soft ... could it be those?

Thanks

It's a WRX classic wagon, by the way!