Hi,
1. Do you receive any error messages?
2. Did you make any recent changes on your system prior to this issue?
3. Do you face this issue with other USB devices also?
I would suggest you to try the steps mentioned below and check if it helps.
Method 1: Run fix it.
Hardware devices are not working or are not detected in Windows:
http://support.microsoft.com/mats/hardware_device_problems/en-us
If the issue still persists try the next Method.
Method 2: I would suggest you to try the steps from the link mentioned below.
Tips for solving problems with USB devices:
Note: The same can be applied for windows 7 also.
Original Title: Logitech S-150 Digital USB Speakers the capatibilty center says my speaker are compatibile but logitect say it only needs usb drivers i just reinstalled my usb drivers from sony still. Download the latest Logitech Speaker System S150 Digital USB S-0218A device drivers (Official and Certified). Logitech Speaker System S150 Digital USB S-0218A drivers.
Method 3:If the issue is still not resolved I would suggest you to remove and reinstall all USB controllers.
To remove and reinstall all USB controllers, follow these steps:
a. Click Start, in the start search typesysdm.cpl in the Open box, and then click OK.
b. Click the Hardware tab.
c. Click the Device Manager button.
d. Expand Universal Serial Bus controllers.
e. Right-click every device under the Universal Serial Bus controllers node, and then click Uninstall to remove them one at a time.
f. Restart the computer so that windows install the USB controller drivers.
Logitech S150 Speakers Too Loud
g. Plug in your USB, and then test to make sure that the issue is resolved.
If the issue sill persists I would request you to check for chipset driver updates which you can get at the manufacturer website.
Logitech Digital Speakers
Hope this information is helpful.