The developer's preview release now includes M3U playlist support. You can find it
here.
Playlists will show up in your music folders. Selecting one will start the playlist playing in the audio player. I don't use playlists that often myself, so I wouldn't say it's been thoroughly tested. I created my test playlist with Winamp. Your playlist should include either full paths to the mp3 files or relative paths relative to where the m3u file is located.
All feedback is greatly appreciated!
-JT
Roku Community Streaming Expert
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