Sigma Rear USB-C port dead

Hello all,

I've had 32GB Sigma board for about a month running Ubuntu 24.04.1. Up until a week ago I had my LG 27UP850 display plugged into the rear USB-C port (power for the Sigma comes from the barrel jack that came with it). The display was suddenly not detected (including it's USB built-in hub) while plugged into the rear port. When I swapped the USB-C cable to the front port, everything worked fine.

I've tried a few different USB-C devices in the rear port. They all power on, but the OS doesn't detect them. It doesn't seem to be an OS issue since the bios screen doesn't come up on the rear USB-C port, only the front.

Any suggestions?

sigma ~> lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 003: ID 3343:803a Unknown LattePanda Leonardo
Bus 003 Device 005: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 003 Device 007: ID 3434:d030 Keychron  Keychron Link 
Bus 003 Device 009: ID 8087:0033 Intel Corp. AX211 Bluetooth
Bus 003 Device 010: ID 0bda:5411 Realtek Semiconductor Corp. RTS5411 Hub
Bus 003 Device 011: ID 05a7:40fa Bose Corp. Bose Revolve SoundLink
Bus 003 Device 012: ID 3434:0ad1 Keychron Keychron K13 Max
Bus 003 Device 013: ID 043e:9a39 LG Electronics USA, Inc. 27UP850 - WK.AEUDCSN - External Monitor 4K
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub