s88 MK3 keyboard not playing on Kontact, but fine on other VSTs

Ginso100

New computer, new build, new mk3. Updated everything. When using either Komplete Kontrol or Kontakt in Cubase, the knobs and instrument controls work fine, but the actual keyboard doesn't register notes. Some sessions it does, some it doesn't. Then if i switch over to a different VST - say Pianoteq - it plays no problem at all.

Its obviously making a connection since the knobs work, and the keybed clearly works because it works on other vst's with no problem.

I am connected via the supplied USB cable directly into the PC. Haven't plugged in additional power since i didn't think that was the issue, given everything seems to work with other VSTs.

any help?