I have a Nanao 2930 in on one of my Blast Cities. After the monitor warms up for 5-10 minutes in 15khz, it appears that the vertical lines start getting all squiggly. I am not sure how to describe it, so pictures of the test pattern below. I tried in 31khz and dont seem to get the issue. Never owned a tri-sync display before, so not really familiar with this chassis, but have repaired dozens of them and never really seen symptoms like this before.