Hi, advanced users.
I'm very scared now because I made a search for the same topic and all of them have not answered. So, if this is a problem with no solution, please at least answer to me that it is so. then I can maybe just give up.
So, here's my video playback patch. I get the impulse from supercollider to trigger the loop in jitter. I don't think it's the problem from that fact as the other player that also get triggered by supercollider via osc works well. (the other player uses "frame $1", jumping to frames at each triggering instead of loop.)