I had to update my system because a piece of software I had installed from the software center didn't work (it didn't open neither graphically nor through terminal), and when I uninstalled it, the (updated I reckon) libraries didn't, and this also broke my virtualbox app which I highly rely on to run windows since I'm a student. So I updated. That didn't fix my virtualbox, and it also broke my sound. In the sound setting all I saw was "Dummy Output" whereas before it said "Speaker playback".
So I was like "Like hell I'm going to troubleshoot this", so I wiped and fresh installed with an iso/usb I had downloaded/made back in December. Then I updated (the update process stopped working through the middle: I was monitoring with the system monitor, and the network graph just flatlined... it wasn't downloading any packages. So I closed, restarted my laptop, and updated again. This time it worked cuz it had already cached all the previously downloaded packages). I decided to restart, for the sake of it, and lo and behold: sound is broken again. Also, when I disable "Dark theme" on budgie settings, well... dark theme is still here, I can't disable it; this issue was present even in the live usb.
Now I can't even use my saved windows10.vdi in virtualbox.
I get this:
Kernel driver not installed (rc=-1908)
The VirtualBox Linux kernel driver is either not loaded or not set up correctly. Please try setting it up again by executing
If your system has EFI Secure Boot enabled you may also need to sign the kernel modules (vboxdrv, vboxnetflt, vboxnetadp, vboxpci) before you can load them. Please see your Linux system's documentation for more information.
where: suplibOsInit what: 3 VERR_VM_DRIVER_NOT_INSTALLED (-1908) - The support driver is not installed. On linux, open returned ENOENT. "