Left and right audio channels switched in analog output on Libre Computer Renegade

I'm using a few Libre Computer Renegades as headless servers, and they're working well (thank you!), but I'm wanting to set one up for personal use, and I've discovered that when I plug headphones into the analog audio jack, the left and right channels are reversed.  (Also, the default volume, (for example, from speaker-test in a terminal) is too loud for headphones.)

sudo armbianmonitor -u

Says:

System diagnosis information will now be uploaded to https://paste.armbian.com/Error adding document.

so I've attached armbian-hardware-monitor.log instead.

armbian-hardware-monitor.log