5.1 works great with movies via the optical output.
5.1 comes out of the box and ends up at the AVR (Onkyo TX-NR 626).
In games, however, the "Dolby Digital Live" coding is required, hardware is provided in accordance with which the can.
This LogiLink USB Box can not do this, alas!
In games only 2.0 / Stereo is transmitted.
So if you want to enjoy the full Dolby gameplay via the home theater / AV receiver (via the optical output), is wrong with this unit.