All of the DEC3000 series support Baseboard Audio.
Currently, only the DEC3000/300s have internal speakers (the machines in the Glue Open Lab AVW 1454)
The DEC3000/400s and above have a jack on the back panel marked with a telephone symbol which is designed to accept the plug from a telephone handset.
Some of the AlphaStations have been shipping with the Microsoft Sound Board which should now be operational. AlphaStations without this board will not have audio capability.
The mme utilities are installed in /usr/bin/mme.
To play a sound, here's an example:
/usr/bin/mme/audioplay -f /:/system/common/multimedia/sounds/wheee.au
Also, two other useful utilites: