One of the machines here with a soundblaster has this in its plan9.ini: audio0=type=sb16 port=0x220 irq=5
Only Soundblaster 16 and compatible cards are driven by #A with type=sb16. With type=ess1688, #A will drive ESS 1688 and compatible cards. No other sound cards are supported by #A, so nowadays people seem to be using USB audio devices via usbaudio in usb(4).
