(Stefan, on Jeff's computer) The FSS wasn't locking anymore, because H1:PSL-FSS_TPD_DC_OUTPUT fell below the threshold value of 0.5V. Attached is a 90day trend of the H1:PSL-FSS_TPD_DC_OUTPUT and H1:ALS-C_FIBR_INTERNAL_DC_POWER. Both channels thow the same trend, i.e. the power loss is real. For now I lowered the threshold to 0.4V.