I am currently using the base image from the Armbian website (XFCE Bookworm variant) which is clearly not on the most recent kernel. For the power source, I’m using the Waveshare UPS HAT (C) for Raspberry Pi Zero (5V). I’ve been using the same unit with the Orange Pi Zero 2W and never had any issues with USB host mode, with them it's an official overlay already.
I switched to the Banana Pi because you guys offer better support, and the presence of eMMC was a big plus. So I don’t believe the power source is the issue, since the other USB port has never failed with the UPS.
I currently don't have access to the device, but tomorrow I will switch to the latest kernel and test with edge if necessary. I had previously avoided newer builds because, about two weeks ago, I ran into an issue with modem detection using mmcli on the latest kernel and build. After switching to the older kernel, the one currently available on the website, my modem was detected again with no changes whatsoever.
Thanks a lot for the quick response. I’ll follow up tomorrow. Great work, by the way, on the BPi M4 Zero and Armbian in general, you’ve been really active.