Windows goes mute after 5 minutes and comes back after reboot

Its been happening for about last two weeks on my wife's Acer Aspire 5551 Windows 7 Home Edition x 64. Windows goes mute after about 5 minutes, when I did sound test I can see bars were moving but no sound coming from speakers. Sound comes back after reboot but goes off after about 5 minutes. So far I have tried : new Realtek drivers, system restore, usb sound card, external speakers, using headphones in hope that maybe that solves that but nothing seem to be working

Any ideas ? I would very grateful as I got no clue what else can be a cause of that

Thank you, I have checked that last night and everything seem to be normal yet there is no sound. And the same again after reboot, sound came back for about 5 minutes and was gone again.

7932 said:

Its been happening for about last two weeks on my wife's Acer Aspire 5551 Windows 7 Home Edition x 64. Windows goes mute after about 5 minutes, when I did sound test I can see bars were moving but no sound coming from speakers. Sound comes back after reboot but goes off after about 5 minutes. So far I have tried : new Realtek drivers, system restore, usb sound card, external speakers, using headphones in hope that maybe that solves that but nothing seem to be working

Any ideas ? I would very grateful as I got no clue what else can be a cause of that

Since you tried a USB sound card, that pretty much narrows the problem down to software.

Maybe some communication app is messing up and telling the OS that there is an incoming call when there is not one. Check this setting:


If the sound still mutes when that setting is set to "Do nothing", then:
...reboot the laptop
...start playing some music
...start Process Monitor* and let it collect data
...stop the data collection as soon as the sound mutes.

Work your way up from the bottom of Process Monitor's data - looking for a reason for the sound to mute. I have no idea what to look for. Hopefully, something will jump out at you. You might try searching for words like level, mute, sound, volume...

* See this post Missing start menu icons on info about using Process Monitor. In your case, you will not want to filter out anything - just yet.

Thank you - have tried and there is nothing in Process Monitor that would give me a clue why Windows go mute.

7932 said:

...when I did sound test I can see bars were moving but no sound coming from speakers.
~~~

Are you looking at the Volume Mixer applet when you see these bars? If so, does the speaker under master (left most?) slider get the normal red symbol on it - as if you manually muted everything?

When I manually mute sounds by clicking on the speaker under the master slider, lots of things change in the registry. There should be one or more RegDeleteKey operations:


Maybe (if we are lucky) the issue you are having will mimic the user manually muting all sounds.

You can...
...start gathering data via Process Monitor
...manually mute all sounds via the Volume mixer
...find the RegDeleteKey operation(s).
Then you will know what they look like for your hardware.

Next...
...reboot the laptop
...start gathering data via Process Monitor

Once the sound mutes on its own, search for any RegDeleteKey operation(s) that look similar to the one that you saw when you manually muted all sounds. Then look at the Process Monitor entries just above the first/similar RegDeleteKey operation for some operation that might have caused the muting.

Also, take note of the precise time stamp in the left most column of Process Monitor for that first/similar RegDeleteKey operation. Then look thru each Windows Event Logs to see if anything happened around that time. If you need help finding/opening the Windows Event logs, see this old post of mine.