Many computer motherboards use Realtek HD audio as an integrated sound controller, providing audio input and output without requiring an add-in sound card. However, on some systems that use Realtek HD, including some laptops, the speakers produce a constant hissing noise. Disabling the PC beep audio resolves the problem in many cases, but hissing may also occur due to wiring issues. If nothing else works, you can use a separate sound card to avoid the problem.
Disabling the PC Beep
The PC beep sound level controls your computer’s internal speaker, which has very little use in a modern Windows system — many laptops don’t even include an internal speaker. Muting the PC beep can resolve hissing from your speakers with Realtek HD. Open the “Sound” control panel in Windows, click “Speakers,” and then press “Properties.” On the Levels tab, drag the “PC Beep” slider all the way to the left, or click the speaker icon to mute it. Press “OK,” and then close the control panel.