Strange oscillation when initially switching on minitaur

This is going to take some explaining :slight_smile:
I use my roland pk5 pedals to play my minitaur and also to send patch change info to it.

When it’s initially switched on I chose the sound that’s in preset location 2. It’s the right sound but it’s oscillating. If I then select a different patch, play a note and then go back to the patch in location 2 it sounds ok. What’s going on?