Comment 12 for bug 1246092

Adding this line before executing audacity fixed the problem completely for me, without disabling pulseaudio or changing the output hardware:

env PULSE_LATENCY_MSEC=30 audacity

I give credit to this post for the fix: http://discourse.ubuntu.com/t/call-for-confirmation-audacity-pulseaudio-issues-on-13-10/969/6