20 valve turbo boost power loss

[shaker]

Hope someone might be able to help me with this problem.
The car was running great up until a few weeks ago then i was hitting peak boost .8 bar then it levelled out at .7 bar.The car then started to feel as though it was towing something and it was being held back and boost is peaking at .3 bar I have checked for leaks and cant find any and if i reset the ecu it goes back to normal for about 5 mls.
thanks for looking and hope someone might have the answer

 

[BCM]

You got VAG COM or access to it?
Tried checkin the DV?
What are you using to measure this? Is the car mapped? What revs does all this happen?
Much much more info needed!

 

[shaker]

Yes i have vag com the only code that comes up is secondary air
The car is not mapped
It happens from 2000rpm
And the dv seems to be fine