The sound I was hearing was intermittent, every 5-10 seconds so I'd guess that when the computer is in sleep mode, no signal is sent to the monitor and therefore it goes through its cycle of checking each input for a signal in turn. So I had a little play around with the settings and while there was no 'quick power-on' function, I found that changing the input selector from 'Auto' to 'DVI' (or whatever input is being used) has totally fixed the issue! Well, one idea was that some monitors have a setting to make them turn on faster - when this is on, the lighting component is constantly heated so it turns on faster (doesn't sound great for the environment!). I've just found the solution to an irritating problem with one of my computer monitors that makes a high-pitched sound when the computer is in sleep mode.Ī quick Google search showed quite a few people were having this issue with various brands of monitors (mine's an iiyama) and the general solution seemed to be 'they're only $100, buy another one'. High Pitched Noise From Computer Speakers Views: 10219 Published: Author: Noise Speakers Pitched From High Computer About From High Speakers Computer Noise Pitched.

Computer makes high pitched noise