Audio support on Cucumber Linux is provided by ALSA. The following packages enhance the functionality of ALSA and are available in Pickle:

lib-base/alsa-libs
apps-base/alsa-utils
lib-base/alsa-plugins
lib-base/alsa-firmware

Only root and members of the audio group are allowed to access the sound card though. If you want to be able to play and/or record audio as an unprivileged user, add yourself to this group by doing something like usermod -aG audio <user>.

The volume can be controlled from the command line via the alsamixer program. Sometimes ALSA mutes the speakers by default so make sure to check here if you are not getting audio playback.