I recently moved my previous install of Linux Mint 18.1 from a Dell Inspiron to a newly bought Dell XPS 9360, connected to a Lenovo Thunderbolt 3 Dock, which hooks it to all my peripherals and an external monitor (Dell 27" 4k, connected via the dock's HDMI port).
HDMI video is working consistently (I get 4k at 30hz), but sound used to work perfectly and now it's erratic. It worked right out of the box after moving, then stopped working. Same with my USB headset. Sometimes the audio options are recognized in PulseAudio (3 different outputs for HDMI 1 for the Headset) but still don't work, sometimes they are just not there. I upgraded to 18.3 in the hopes of it getting fixed, but nothing.
Everything works perfectly if I boot from an Ubuntu Live USB so I think this is probably just a layered issue of software being added/removed for years in my previous install.
How can I "reset" the state of audio/video drivers and configs as if I was in a fresh install without actually reinstalling the whole system?