Unfortunately, the pulling the knob out did not help. I tried this with different pressure, being conscious though....
I needed integrated amp to be used for both purposes: as part of cinema set up through pre outs, and stereo music listening from direct sourcing (mostly digital).
I found this amp potentially serving the purpose. As stereo amp it's just great (compared to PM6006), but it cannot serve as component of cinema set up. As I understood it wasn't supposed to.
Thank you for the help!