Which Linux Distro?

[Jostein]

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What distribution are people using these days? Should I use UbuntuStudio? They were having issues a year or two ago, but maybe they are solved now?

You can probably use any new mainstream Linux distro you want and just use a Low Latency or RT-kernel. Personally, I prefer Kubuntu and the two main reasons are: 1: I like the KDE desktop and 2: Ubuntu's big user base almost guarantees that you programs work, problems will be fixed quick and that any binary package (I have Mixbus, Loomer Aspect, Pianoteq and a few more) works.

Jostein