When I connect my external monitor (ASUS PA248) to my W520, the audio from W520 disappears. When I disconnect it, the audio returns. This seems a bizarre link between audio and video, but there it is. Note that the PA248 does not have built-in speakers.
Does anyone have any idea?
Check if your sound settings are activated properly.
To do so, proceed with the following:
Go to Control Panel >> Hardware and Sound >>Sound>> Change System Sounds
Go to the Playback option and check if your system's internal system speakers have been selected as Default.