Hi Geert,
ModThing and DelayThing have a two stage bypass which allows you to mute just the input to each effect. This is a better option for switching since there is no audio dropout. There are some notes on the last page of the User Manual:
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The bypass switch for both ModThing and DelayThing uses a special two-stage switch. Stage 1 bypass mutes the device input, and Stage 2 bypass removes the device from the processing chain. Stage 1 bypass is particularly useful for live performance when you wish to switch out a delay unit without cutting off the effect repeats.
The following table shows what values should be sent via automation/MIDI in order to trigger each stage of bypass.
Automation (Audio Unit) MIDI
Stage 1 Input Mute 0.5 63
Stage 2 Full Bypass 1.0 127
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Let me know if this does the job!
Cheers,
Mike.