bbps1:2001 - slot15 chan:11 bbps1:2002 - slot5 chan:9,10,11
I checked the high voltage on the T7 trigger, they were off. Infact I switched them off quite some time back when I figured there was no signals from three PMTs(may be broken base?).
All four PMT signals go to amplifier before they are discriminated and the thresholds were also very high(~-200mV) - hard to imagine the noise on PMTs is creating bursts of signals.