Interestingly I've just tried Kubuntu 20.4 in a virtual machine and my helix is showing up without any additional configuration. Going to upgrade my workstation and see how well it works.
I've updated the to 20.4 on my main workstation and Helix is connected and working. I'm new to using audio on linux, I've only just moved across from windows so am still learning all about it but Helix seems to work straight out of the box with Kubuntu 204. The screenshot below is from my main workstation.