Unexplained lockloss. Winds at 20mph, microseism 0.54 μm/s.

No oscillation in PSL channels like TJ saw earlier his week, however there is a spike in ETMX L3 output channel 1 second before lockloss (see red bottom left trace in attached plot). There have been a few cases of a spike in L3 then lockloss (2020-01-20 00:10:04 and 16:09:51 UTC). Looking at the oplevs and osem_wit channels, it seems like the suspensions aren't actually moved with the spike but I haven't worked out it's source.