Question: I am running Kubuntu 19.04 on a XPS 13 9380 with the TB16 thunderbolt dock. 

Everything was running fine and I could get audio from the dock headphone jack. After upgrading from FW 1.7.0 to 1.8.0, the audio device from the dock still show as USB Audio headphone and USB audio line out. no sound comes out of the devices. 

When looking at the advance audio setting, i noticed that the only profile available for USB audio is Default. 

any help would be greatly appreciated.

Answer: 
I was able to fix it by installing Ubuntu 19.10 on a different partition, which then - during it's installation - did repair and update the grub.
Similar thing happened to me, I had:

* Ubuntu 16.04 on an HDD (*sda*)
* Windows on an SSD (*sdb*)
* Another Ubuntu 16.04 on *sdb*, but grub was loaded in *sda*.

After I removed my Ubuntu version from *sda*, I could only get to grub terminal, and booting from an Ubuntu USB and running boot-repair didn't solve anything.

Solved it by installing Ubuntu 16.04 again in my HDD, which during installation repaired the grub.