Resolved Loudspeakers don't work after waking up from the sleep mode

I have a pair of USB loudspeakers with no audio cable. A USB hub is connected to a USB port on the motherboard.
If they are connected to the hub, they will not work after the computer waking up from the sleep mode unless they are unplugged and re-plugged.
If they are connected to the port, they will still work after waking up.

Does anyone know why? Does it have something to do with the fact that the ports do not supply power during the sleep mode?

 

(Quote) "Does it have something to do with the fact that the ports do not supply power during the sleep mode?" YES

Failure of USB devices to resume is an identified problem with Windows 7. See linked Microsoft Knowledge Base Article KB 2484742.

USB devices may fail to resume from selective suspend on a computer running Windows 7

You can disable selective suspend:

Windows 7: Turn USB Selective Suspend On or Off

You can change power settings in Device Manager to stop putting USB devices to sleep.

In Device Manager navigate to the USB device. Right click and choose Properties. Click the Power Management tab. Uncheck "Allow the computer to turn off this device to save power."

Some other things you can try:

If BIOS has a "Deep Sleep" option, try turning it off.

Try turning the "Hybrid Sleep" power option off.

Turn Off Hybrid Sleep in Windows 7

Some USB ports are in effect connected to internal USB hubs. Try different ports.

 

NO! "Power" on the USB ports during sleep mode is to allow users to charge their cell phones and such while the computer is asleep.

The speaker's own intelligent input circuits don't use "power" (as in +5VDC) per say. Computer speakers are typically self-powered. They plug into the wall, typically via the subwoofer's internal amplifiers.

The speaker is supposed to wake when "audio" (not power) is detected on its inputs. And it appears your hub is not properly passing that audio.

The fact the speakers work perfectly when connected directly to the motherboard's USB port indicates the USB port and the speakers work fine.

Bottom line - get rid of the hub.

 

Two pendrives on the hub are working properly.
Why can it detect pendrives but not loudspeakers after waking up?

Mine is powered by USB.
(Is it correct to say 'mine is' when 'mine' refers to two speakers?)

 

Detecting a drive is not the same as passing an audio signal to sleeping speakers.

Ah, then these are very small, likely less than 4 watt speakers. But still they use an audio signal to wake, not plain voltage.

Your speaker system "is ", your speakers "are ".

 

Using the same speakers, the same hub, the same Windows and the same settings.

On my old eMachines EL1850 motherboard, whose USB ports still supplied power during the sleep mode, the speakers could wake.
On my new ASUS H81M-A motherboard, whose USB ports do not supply power during the sleep mode, the speakers cannot wake.

That's why I guess it may have something to do with power supply.

 

Your power supply is fine. But you might look in your BIOS Setup Menu to see what it says about USB power during standby/sleep mode.

 

I just looked it up but it says nothing about USB power. The USB ports can be either on or off.

 

Sorry, but I don't have anything else to offer except maybe try a different pair of USB ports. And I might try the speakers on a different computer to see what happens there.

 

I have changed it but the hub still sleeps. May it have something to do with ASPM being off in the BIOS settings?

 

ASPM applies to PCIe serial link devices and Firewire, so I would think not. It is listed separately from USB devices in the power management dialog. (See link which follows)

Windows 7: PCIe Link State Power Management

Are you unable to rearrange your devices so as to direct connect the speakers?

 

I am able to rearrange any USB devices. And I have decided to leave the speakers directly on the port, as I have more than enough USB ports.

 

Good decision.