Describe the bug
With the Valve Index connected and powered, udev rules installed, and latest available drivers, SteamVR is unable to see the headset. I have attempted fixes outlined in other solved issues without luck.

To Reproduce
Steps to reproduce the behavior:

1. Plug in headset
2. Start SteamVR
3. Recieve 108 Error

Expected behavior
SteamVR starts successfully

System Information (please complete the following information):

• Distribution: Pop-OS 20.10 (Ubuntu based)
• SteamVR version: 1.15.15
• Steam client version: Dec 19 2020, at 02:07:08
• Opted into Steam client beta?: Yes
• Graphics driver version: NVIDIA Driver 455.38
• Gist for SteamVR System Information: https://gist.github.com/AnEthernetCable/56df25ea57d897f3315c5c14a4dcc438

Additional context
udev rules: https://gist.github.com/AnEthernetCable/0201be701eb9bf797901e54565febca8 (up-to-date with steam-devices git)
lsusb: https://gist.github.com/AnEthernetCable/9ae0a8666e0dcae2955caf24df319d68
Relevant dmesg: https://gist.github.com/AnEthernetCable/df2fe0a70cb4eaa5efd29a4e91c9ff21

I have read through closed issues, and it appears some others have had bad 3-1 cables. However I have had this issue previously, the issue fixed itself, and it is now back. I just used my headset 2 days ago.

I have tried different Display Ports and USB ports to no avail. Rebooting does not fix the issue. I do not have another computer I can test the hardware on. The HMD LEDs remain blue when plugged in.

Note: Commenters who are also experiencing this issue are encouraged to include the "System Information" section in their replies.