Acer AT3720A AT3720A Service Guide - Page 63

8. Speaker does not have sound H Audio R/L source had plug IN? no Check Audio R/L source cable Video can Display ? no Check Video cable or Replacement Video Cable Mute turn off Volume set 50 Speaker R/L cable plug IN? no Check Speaker cable or Replacement Speaker cable Speaker have Sound Output END no Replacement IO/B or Speaker Speaker have Sound Output ? no Replacement M/B Chapter 4 57