1] Audacity Audacity is a free and open-source audio editing software that lets you add white noise to music. You can import audio files, generate white noise, and then add it to imported audio.

Audacity is great for recording, Importing and Exporting files in a wide range of formats, editing sound files, adding effects, improving sound quality and sound analysis.

FLAC now fully supported. Added support for optional FFmpeg library for import/export of AC3/M4A/WMA and import of audio from video files.