Maybe it’s an SPDIF thing. I’m on OSX, Saffire Pro 40, My main keyboard: K2500XS connected via SPDIF-OPT. Abelton Live 9 Suite records audio just fine. Cubase 9.0 and 9.5? No joy. Only analog ins work in Cubase. As someone who picked up Cubase Pro 9.0 three weeks ago and just upgraded to 9.5 (the grace period is nice, thanks Steinberg!) it’s super frustrating…especially considering the exact same hardware and setup works in the other DAW.