At  ~20:15 on Feb 4th, Hugh switched the GS-13s on ETMY ISI to low gain, and these haven't been switched back since. It's not clear if this impacts the performance of the ISI or not. I've attempted to find long stretches where ALS or oplevs were available to say something about the performance with out of loop sensors, but so far I haven't been able to get a clean before AND after spectra. ISI local sensors don't show any difference (see my plots earlier today showing ETMY vs ETMX suspension point motion, ETMX has always been in high gain). I attach a trend from the 4th to the 6th showing ALS CTRL and one of ETMY's GS-13s. The gain switch is pretty obvious on the GS-13 plot. The best I've been able to find is my second attachment, showing ALS CTRL spectra, dashed lines are high gain, solids are low. Only differences I can see are likely due to higher ground as the solid lines were at 21:20 (3:20PM local). ITMY's GS-13s are in high gain for both measurements, and so could be obscuring this measurment. I'll try to get a measurement with both ISI's in high and low gain.