I’ve found that too. Since USB-C can be used to send power or receive power, there is logic to figure out what needs to be done. If you plug in the (powered) USB-C connector first, it knows to receive power. However if the device is already receiving power (from the battery input or from the 5V input), then it will no longer look for power on the USB-C connector. It seems when that happens, it also decides that it shouldn’t talk on that connector either. It’s annoying, but in my application not a big deal. I can just unplug the 24V power, plug in USB-C, and then plug in the 24V again.
The issue I’m having is the inability to get the XIAO to function at all when only powered by 24V (though it works fine if USB-C was used to get it going, and subsequently removed. I could do this, and it would work, but it’s definitely not what I want.
@PJ_Glasso, might you have any ideas for us? (You were very helpful with the previous issues I was experiencing…)