I was very disappointed by the poor sound capabilities of the GNU Ocatve project compared to MATLAB. The playaudio() function was inconvenient with nasty '/dev/dsp device or resource busy' messages. This was until I installed the octave-audio package in Debian and had the powerful sound() and soundsc() functions working.
The nasty thing is that those functions didn't work out of the box. They needed to call a play command from the shell. Finally, I discovered that this command is part of the sox package on Debian. I apt-get install sox and now, sound() and soundsc() are working perfectly!