RB only uses the default system synth for metronome
So currently you have to use that .. not any other VST or Hardware .
Could that be it?
//personally I make my own click .. just create a measure of MIDI on the desired channel (usually 10), then copy it for the length you want
It doesn't have any lag that way and you can use any synth
Afterwards AutoConvert to an Audio track for best control ..
/// I have a MID file already created called click.mid, I import it into a project as a MIDI track (so it gets the Tempo) then AutoConvert to Audio
Once it is audio it is easier to deal with
For many users, since they have 'Reroute all MIDI' checked it works normally, but it only sends to that default port, you can't assign it anywhere

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