Sounds like a boost leak to me.
I have no experience with Autocom, can you log the data, desired and actual boost and duty cycle?
I would recommend vag com, so much easier for this test.

Aslo the smoke test is no good for finding boost leaks, just not enough pressure. We have adapters made up to fit the inlet side of the turbo using a tyre valve and tyre inflater we can pressurize it as high as we need, then just listen. I know access can be tight and not always practical, but there's usually a way.

Hope this might help.

Chris