I suspect i already know the answer to this but after a spirited drive last night i seem to have now developed a noise in highter gear under boost,

Its like a loud whistling noise, think its coming from behind glovebox when driving, had a quick look round and intake pipe from maf to turbo looks okay as do breather pipes and other feed pipes,

I suspect it still has standard dump valve it came from factory with so suspect that is split inside

Yep sounds like the seal has gone on the DV.

Have you checked the pipes to the dump valve mine pop off now and then making the noise you discribed

I've had a quick check round and carn't see anything obvious

Did you take the engine cover off to check m8? I've got a standard dump valve spare if you need it?

Don't have a engine cover on so can get to most stuff under bonnet

I've got a spare dv you can try, and I'm in wakey most days!

After run to whitby today i think its well shot now,

Am taking car off road for winter this week so thanks for the offer but ill pass