Help with an SPC Error on Tektronix DPO3034

[analogRF]

I had not run SPC on my DPO3034 for a very long time and today i realize that it fails SPC 
It fails at almost the end of the SPC. But self tests always pass even in loops of 10 never fail.
I ran the SPC in manufacturing mode and no difference but I can now get a slightly more meaningful error message in the error log
which unfortunately goes beyond the window  the morons who wrote the FW didn't wrap the text so that it continues on the second line instead of disappearing out of the window....

anyways, using :ERR:FIR? command from the scope's web page I can finally extract the error message as this:

Code: [Select]

846: 3 0 0 Calibrate 22:52:11 03/03/2021 CH4 NREJ comparator A 2mV/div -FAILED- 2mV Trig Hyst Rslt too hi

any ideas? any suggestions as to where I should be looking at? I believe NREJ means Noise Reject mode in Trigger setup
and the rest are pretty much self explanatory except the last two words "too hi"? what is "too high"?

I noticed that if I change down to 2mv/div or 1mv/div on all channels, CH4 has more noise (some spikes actually) than the other 3 channels
Those other 3 channels dont show spike noise

any suggestion is appreciated

[analogRF]

I posted this on the Repair forum. So if you have comment please leave it there. thanks