Unable to connect to iCA4+ with PC on USB1

I want to update the firmware from 1.0.7 to 1.1.0, and iConfig pops up a note stating to ensure the PC is plugged into USB1 before doing so. Up to this point, I've had an iPad plugged into USB1 and my PC (win 10) plugged into USB2.

So I unplugged the iPad and moved the PC's cable to USB1 ... but then iConfig doesn't find the iCA4+ device. I tried rebooting the PC, unplugging and replugging the iCA4+ power, reinstalling the USB driver, all with no luck.

I then reconnected the iPad to USB1, and opened the iConfig iOS app on the iPad, and it connects fine.

So I reconnected the PC to USB2, and connected to iConfig ... no problems. I then did a "Restore to Factory Defaults" and tried connecting again on USB1 ... but still no luck.

I'm using the USB cable that came with the iCA4+, and it works when connected to USB2, so I'm doubtful it's a bad cable.

Any ideas what I can try here? Or is it "ok" to do the firmware update when connected to USB2, even though iConfig states to make sure the PC is connected to USB1?

I already had a support ticket open due to a different issue, so I replied to it asking about this. Just thought I'd check in here to see if anyone has any advice.