Many DVD / MP3 / JPEG players that will play "anything they can" on CD-R, do not extend that capability to DVD-R, playing only correctly formatted DVD material.
If it can handle DVD Audio, then this might be interesting
http://dvd-audio.sourceforge.net/
But it looks like that model cannot.
Only other possibility, is to make a DVD Video with low video bitrate, which should allowquite a few hours of audio that would play on any DVD compatible platform.