@dc42
Upgraded from 3.2 to 3.3b. Only issue I ran into was the upgrade created a firmware directory but didn't move the firmware files from the sys directory. Pretty easy fix for me to move the files but wanted to make sure you were aware of it.
Update seems to have fixed the issue. I did the same M122, M122 B21 during the print and it shows no lost CAN messages. Doing M122 B21 did hiccup the print but no error message and it was much less noticeable than before. toolboard_good.txt
The print also came out similarly to when the extruder is wired to the mainboard. I was getting worried that the problem was my mainboard, thanks for the help!