To work with PulseAudio, Audacity requires the pulseaudio-alsa is installed. This provides the
pulse:... playback and recording devices.
When starting Audacity you may find that your headphones no longer work. This can be because Audacity is trying to use them as a recording device. To fix this, open Audacity, then set its recording device to
pulse:Internal Mic:0 .
Under some circumstances, playback may be distorted, very fast, or freeze, as discussed in the Audacity Wiki’s Linux Issues page.
The solution proposed in this page may work: start Audacity with:
$ env PULSE_LATENCY_MSEC=30 audacity
If the solution above does not fix this issue, one may wish to temporarily disable pulseaudio while running Audacity by using the
$ pasuspender – audacity
Then, be sure to select the appropriate ALSA input and output devices in Audacity.
See also #Setting the default fragment number and buffer size in PulseAudio.