audacity 2.4.1 won't recognise focusrite scarlett solo on ubuntu 18.04.3

i recently updated to audacity 2.4.1 on ubuntu 18.04.3 and i can not get my focusrite scarlett solo to work at all…
it did work when i was on audacity 2.2 (same ubuntu)
any ideas? is this a ‘bug’ do i have to install additional drivers ?

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