I have just bought a Behringer USB Xenyx mixing desk which has USB audio connections (and windows driver).
In Cubase, I have loaded this devise in the Devcice Setup/VST Audio System and it shows both input and output ports active. I have mapped them as relevant in the VST connections. All looks good. When I play an instrument connected to the mixer, Cubase recognises the input signal and records it successfully. But, when I try to play back [into the mixer], I get nothing.
Interestingly cubase’s mixer shows no activity on the output when I play the track - so my guess is that something is not configured right in Cubase or the USB driver somewhere.