Built in Mic isnt working DELL LAPTOP - Windows XP

- Right click My Computer
- Click on Properties
- Click on Hardware Tab
- Click on device manager
- Find your sigma tel sound driver in list
- Right click on your sound driver and click properties
- Click on unistall and click on OK button
- Click on Action menu in device manager window
- Click on scan for hardware changes
- Now again point your cursor to sound driver in the list
and install the driver
- It will start working ;-)