Been getting the exact same issue as OP last few days. Havent got any error codes or anything but car is the same in the same rev ranges. Seems to boost about the same still but I did notice sitting on 110km in 5th it sounded a bit louder and pingy.
I took out maf and cleaned it but the dam rubber ring has broken in a few places so I just had to put plumbers tape in it for now until I can get one from sca or something since BP didnt have any
I will have to put in my obd2 thingy and go for a drive later, but im not really sure what to look for.
Possibly some issue with intercooler piping, i check the ones I can reach but not all of them since its fmic I think I might have to take it for a service.