As a ‘work around’ rather than totally disabling pulse audio, did you try launching audacity (only) with pulse audio disabled only for that app (audacity)?
i.e. something like:
pasuspender -- audacity
I don’t know if that would work, but as a ‘work around’ its worth a shot. Ultimately thou, you need to sort out why audacity is not recording for you. I suspect a pulse audio misconfiguration somewhere.