So: Eventide – you must be aware of this glitch. I get that it's not as sexy (or lucrative) as a new algorithm (and yes, fair play, I love HotSawz too …!), but this is a pretty fundamental fault. What's the situation, please …?

OK, I've tried it with my H9. Here is the thing:

I guess your MIDI controller must have sent two messages to your H9, one is MIDI CC 10 with value 127, which bypasses your H9. However, when you release that switch on your controller, it sends another MIDI message CC 10 with value 0, which activates your H9 again. You should be able to prove my theory and reproduce it by presssing and holding the switch and see if that bypasses your H9, and if releasing it would unbypass (activate) it again.

So 2 sulutions:

1. Set your MIDI Controler to only send 1 MIDI message (CC 10 value 127) when you press the switch on your controller.

2. This is more like a workaround. Map MIDI CC 10 to "Activate" in H9 Control. Then when you press the switch and release the switch, it will activate and then unacitve (bypass) your H9, which is what you want (to bypass your H9).