Acer AT3720A Service Manual page 68

13. VGA/DVI no sound
PC/DVI can Display ?
Turn off Mute function
Volume set to 50
Audio Line in
Cable Plug IN?
Sound Normal ?
62
M
END
no
Check Video cable or PC or
Replacement VGA/DVI cable
Check Line in cable or
no
Replacement Line in Cable
no
Replacement Main/B
Chapter 4