I don’t know if this has been reported before, but the keyboard octave buttons on my Sub (as we now officially call it 
) just died. I was using it with Maschine, the unit being connected to my Mac via USB. The LFO modulated the waveform with the mod wheel being in maximum position. First I had turned the sub oscillator all the way up, then I decided to turn it down and lower the keyboard octave instead (from 0 to -1). When I did that, it suddenly switched to the lowest octave and didn’t react to the buttons anymore. When I pressed the “octave up” button, the -1 light just flashed briefly and that’s it. Everything else was still behaving normally.
I powered the unit down and up again and the issue instantly occurred a second time when I tried to alter the keyboard octave. I turned it off and on again but also moved the mod wheel this time which apparently solved the problem - but that might well be coincidental.
I’m using firmware 1.2.8 if that’s of any help.