P0299 Low boost woes

[Han solo]

Hi all,
Looking for some wisdom, or possible the location of a good cliff to push the car off.
The said car is a 2012 D5 2.4 V70 300k miles
It drives great upto 2500 rpm then it has a dip in boost and the error code comes up along with limp mode.
I've checked (as much as I can) the boost pipes and vaccum lines and can't see or hear anything obvious, I've cleaned the map sensor on the inlet manifold....I did clean it a while before the problem, are they easily damaged?
The vac line from the air intake looses pressure when I attach a gauge is this normal?

I took it to a local Volvo specialist, he plugged it in and gave me a detailed diagnosis "it's not making boost"

I've run a cheap diagnostics tool on my phone and the desired boost and the delivered boost track quite nicely until you accelerate hard, the desired boost hits about 40psi the delivered flats out at about 32psi before error.

I do have a Vida unit but not entirely sure what I should be testing or looking for, so any ideas would be much appreciated.
Cheers,

Paul.