Windows Media Audio 9 Lossless is a lossless incarnation of Windows Media Audio, an audio codec by Microsoft, released in early 2003. It compresses an audio CD to a range of 206 to 411 MB, at bit rates of 470 to 940 kbit/s. The result is a bit-for-bit duplicate of the original audio file; in other words, the audio quality on the CD will be the same as the file when played back.