The Windows Media Stream Editor, a component of the free Windows Media Encoder is available from the URL below:
This tool can extract the audio from a .wmv video file and save it into a standalone Windows Media Audio (.wma) file. Follow the steps below on how to extract audio from a WMV video file.
First, open the Windows Media Stream Editor and click Add Source. You can also drag any .wmv or .asf file to the window:
image
Select the output tab then specify the filename of the output:
image
When you’re ready, click Start Encoding button to begin the extraction.
image
When the process is complete, you’ll have a standard .wma file.
To extract the audio track from non-Microsoft video formats, you’ll need a different program. A full-blown video editing application like the two popular choices below:
But if you want to do it for free, try the AoA Audio Extractor: