Four mk2 first notes of playback ignore channel's sound settings

So I restart playback and the channel play the right midi with some funny sound, okay but not matching the tune and not ones I have set. after a couple of rounds the sound becomes what I have chosen.

I have taken extra steps to sort this out. As the sound gets back to normal, I saved the sound, kit and pattern. This should do the trick but it does not.

I have checked the locks and there is nothing activated in the first round or otherwise diminish frequency of note playback, which might be carrying wrong-sound locks.

1.5c, and I have come across this for the first time.

What could be the issue?