it was an UP leak.
my mechanic somehow "forgot" to put the nut on the stud in front of the turbo.
got it on there, tightened it up and no more fine knock or feedback knock.
from what I understand this leak was causing conflicting signals to the front and rear O2 sensors and thus causing the problems.
I still think my tune is running a bit rich based on my AF Learning A-D readings, but I plan on getting over to a dyno asap to get all the fine tuning done.