Hi,
1. What is the make and model of your computer?
2. Have you installed the latest drivers from the manufacturer website?
**Step 1:**Try installing all the available Windows Updates and check for the issue. To do this, follow these steps:
1. Click Start, All Programs and then Windows Update.
2. Click Check for Updates on the left of the screen.
3. If any updates are available, go ahead and install them.
**Step 2:**Try running the Audio Troubleshooter and see if it helps. Refer the below mentioned link.
http://windows.microsoft.com/en-us/windows7/Open-the-Playing-Audio-troubleshooter
**Step 3:**Log on to the manufacturer website and install the latest available drivers.
Regards,
Syed N – Microsoft Support
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