User guide

Although the sbpro driver supports A-law encoding on AD1848 and compatible
devices, audiotool does not and produces an error message if you select A-law
encoding. Use audioplay(1) to play A-law encoded audio files, or use
audioconvert(1) to convert the A-law sample into a format that audiotool
will accept, such as 16-bit linear. User-written applications can select A-law format
using the sbpro driver on AD1848 and compatible devices.
Compaq Deskpro XL Business Audio With Built-in AD184x Chip
Some system units have the headphone jack wired with its Left and Right
channels reversed, so you hear Left output in your right ear and vice versa. The
line-out jack at the back of the unit works as expected.
The quality of sound is better when using an external microphone and speakers,
not the ones built into the keyboard.
Device Reference Pages 97