FYI:
Last night I taped a show and thanks to a loud clapper

I realized the left and right channels of the recording were swapped.
I did some testing of the JB3 just now, and it appears the level monitors on the JB3 swap occasionally. Sometimes they show the correct channel, and sometimes they show the opposite channel. Last night I only checked the monitors on the JB3, so I didn't realize I was running my mics reversed. I knew the JB3 monitors were bad, but I assumed they showed the correct channels. It appears I was wrong.