We have had a number of events where SR3 jumps suddenly and has a DC alignment shift. Attached are some plots of one of these events that happened at 1330369950

The first plot shows the inputs from the top mass osems, they all see a DC shift and none of the osems seem to be glitching.  This is different behavoir than a problem that has come up several times with SR3 in the past, where one osem seems to glitch 32328 45175 and 32220

The second attachment shows that there was no DC shift requested at the time (the top mass master outs had no DC shifts) and that this wasn't coincident with a HAM5 ISI trip.  (We have tripped the HAM5 ISI today, but that was not at this time). 

The third attachment shows that these shifts have been happening occasionally over the last 20 days, possibly for longer.  Some of the shifts shown by the oplev in this longer trend coincide with ISI WD trips, but some of them happen when no watchdogs are tripping. 

Another alog with some strange behavoir of SR3 is here: 56436