We need to find out if the problem is in the monitor or at the PC sound card. Try feeding the monitor with sound sound source such as MP3 player to the audio line in of the monitor to see if you get the sound or not. If you do not, then you will need to open up the monitor and inspect the audio power amplifier circuits. If you get the sound OK, then verify that the cable between the PC audio line out (green jack) and the monitor audio input (green jack), next verify that the audio level controls (on screen volume control panel) are set up OK, not at minimum setting. Verify that correct driver for the sound card is installed.
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We need to find out if the problem is in the monitor or at the PC sound card. Try feeding the monitor with sound sound source such as MP3 player to the audio line in of the monitor to see if you get the sound or not. If you do not, then you will need to open up the monitor and inspect the audio power amplifier circuits. If you get the sound OK, then verify that the cable between the PC audio line out (green jack) and the monitor audio input (green jack), next verify that the audio level controls (on screen volume control panel) are set up OK, not at minimum setting. Verify that correct driver for the sound card is installed.