If you're only sending and don't need to receive any MIDI, you can turn on Settings > Advanced > Ignore MIDI Input. That will discard the beat clock messages before they reach the activity log.
If you want to send some initialization MIDI only at the start of the show, you could attach that MIDI to your layout and trigger the Send Layout MIDI function from a layout gesture like three-fingered tap or from a remote control device like a foot switch. Alternatively, you could make a song that contains that preset and has a duration of 0:01 and put it at the start of every set list. Or the simplest option is to go to the Repertoire > MIDI Presets list while you're setting up, and click the MIDI icon for that preset.