Open hi hat, cymbal, and snare triggers hand clap

[synthead]

[gazcbm]

Is the trigger occuring all the time or occasionally? Is this issue still open?!

[pouek]

I also had a problem of unwanted triggers with my first mod using gate inputs instead of midi, and 4066s instead of transistors.
I fixed it by adding series resistors before the 4066s to prevent interplay between the inputs.
I guess with proper taming / pull-up-ing / pull-down-ing it should stop.