Sony PCV-RS730G - Manual (Page 112)

Why do my song information edits revert to the original content when I use My Music?
When you record songs with SonicStage software, and then use Windows ® Media Player software to edit the song's
information, you may not see your changes when you play the song in My Music. Windows Media Player supports playback
of songs recorded in OpenMG (ATRAC3 or ATRAC3+ ) format, but does not support any edits made to the OpenMG format
music files. Use SonicStage software to edit song information for music files that are recorded in OpenMG format.
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