When changing KBD_OCT, user gets unhelpful feedback of which key is down

[nealmcb]

If I set KBD_OCT to +1, and hit the leftmost key (C), I don't see that key get highlighted to indicate that it detected my mouse action. Instead, the C key near the middle is highlighted, presumably because the synthesizer is playing C3, 131 Hz, just as it would if I pressed that key without changing the keyboard octave.

This is especially problematic when I'm trying to play a chord on a multi-touch device, since with significantly distorted synth settings it is actually not clear whether it detected each of the keys I meant to press. And for many settings, no keys are visibly highlighted at all.

Please highlight the keys I'm playing, rather than highlighting the key from the unmodified keyboard corresponding to the note that is playing.