VSDC is one of the best free video editor for Windows at present time. It has all tools you need to edit video such as: cut, trim, crop, merge clips as well as adding transitions, effect to the video. One important feature of VSDC is the possibility to adjust the volume of the soundtrack partially. This means that you can increase or reduce soundtrack volume at different point on the timeline.
Learn how to adjust soundtrack volume in VSDC from this tutorial video.
If you want to discover more about VSDC, take a look at our full review here!