Comment 3 for bug 178256

I was just going to open a bug report for this one. Indeed, Psi defaults to using "play" as the application for sound events. On a default Ubuntu installation, with Psi added, the "play" command is not present. However, as the previous poster has noted, changing this to the alsa player "aplay" works perfectly.

Additionally, this problem is present in Gutsy as well as the reported release.

Please consider making "aplay" the default player used in the Ubuntu Psi installation.