I have tried the unplugging in the boot 'golf tee mod' alternative and it makes little difference so maybe that is an indication that the actuator is buggered.
I am planning to get my turbos rebuilt (wastegate rattle) and fit downpipes at the same time to save on labour (hence the WTD in classifieds), and of course spending that much money it would be nice to have some performance gain. I have the Evolve-R cable so will get those guys to sort em out a new map. I'm happy with the noise which is why it's hard to justify so much money on a new exhaust and to an extent turbos just to stop an embarrasing noise.
Do you think there is a way of just cutting the flap out of the stock exhaust if it is close to the back?