Sorry to hear that. It means the music won't be supported on dingoo unless someone tweaks the bitrate or the quality of the music. Although in theory it could run fine on GCW Zero as it is.
Do you have the source code for OpenDingux version available somewhere (git?). Or can you please upload it?
Just in case someone wants to tweak it.
By the way, thank you Zear for the work you have done. It's pretty cool to play Cave Story on Dingoo.