My AVC-r hits 1bar at around 68%ish duty cycle. I run 1.25bar at close to 78-80%. there will be some variations of this setting due to setup from car to car.
I would remove the intake pipes to the turbos and feel the shaft to see that it spins freely and does not have excessive shaft play. this will give you the best idea if its turbos or something else. It is tight to get down to the intake of the turbos but I have done it so it can be done. and its better then pulling the motor to check the turbos and then find out that the turbos are OK.