Sorry to hear of your disappointment. I am unable to reproduce your issue, I never experience a gap in the audio when I am sending a constant tone to the H90 from a synth and changing Programs using the footswitches or a MIDI controller.

If you’d like to troubleshoot this further, can you please email support@eventide.com and provide full details of your setup, and if possible audio and/or video examples of the issue would be helpful.