Jim W. pointed out that there was an oscillation in the control loops. ETMX ISI seemed to be moving quite a bit as well. This grew to the point that we knew we were about to lose lock. Nutsinee suggested an increase in DHARD gain by 3dB (based on a previous experience she had, and advice from Jenne and Sheila then). I changed their gain and after about 10 seconds or so it dropped.

The ETMX ISI is still has large movement in it, and not showing signs of relaxing at all. The control room is working on it, we will try to relock again as soon as we can.