From Just Solve the File Format Problem
RK Audio is a proprietary lossless and lossy audio file format created by RK Software (later M Software). It is related to the RK compression format.
Files apparently start with ASCII "
- RK Audio v1.07 (for Windows console, includes Winamp plugin)
- MediaInfo - displays technical and tag data for media files
- RK Software - RK Audio page (Wayback Machine capture 2005-02-07)
- Info for RKAU files. A patch for MediaInfo adding support for RK Audio files.