ARGH.... I finally found out what is that regular noise, the probes reset to AC coupling. I haven't looked in the manual yet if there's a way to save the current setting as Default.




About the uneven edge spacing, it's mostly the A wiper (yellow) that varies a LOT. B wiper seems to remain stable on average (sometimes it gives a longer intermission, but nothing as radical as A wiper).

I don't know if it's me that damaged the rotary encoder, or if it's "cheap" that way. I turned it countless times both directions, and I don't find a pattern.

If I turn CW and get a long intermission, I turned 2 clicks CCW, then turned again CW, but didn't get the long intermissions again.