Output Monitor Speakers

Hello Forum,
since one i use Ardour and a Steiberg UR12 under Ubuntu Studio 20.04 without big issues. My setup is really simple. Steinberg Audio Interface is connected over USB on PC and my active Studio speakers are also connected on PC over USB. Two days before i installed the newest firmware on the Audio Interface and now output works only over the headphone or Line-out from Audio Interface. I tried on a second PC and have the same issue. I tried different settings but no luck Did anyone has a idea what i can do or try?

Sorry for my bad english.

Thank you
Mat