Int 48 Fn 01  - Ti Professional Pc - Speaker Device - Check Speaker Statu  [b]

   AH = 01h

Return: ZF clear if speaker is currently on
   ZF set if speaker is currently off

See Also: AH=00h,AH=02h,AH=03h,AH=04h,AH=06h,AH=08h,AH=0Ah,AH=0Bh