@tommysammy
AFAIK, it is a limitation of DiskGui AND of the CD image formats:
ISO images cannot contain audio tracks. Some software allows ripping them separately as MP3s, and then storing how these tracks are arranged on CD using a CUE file. Super Stardust CD32 contains such an example:
http://www.dream17.info/downloads.php?cat=2But I don't think DiskGui supports CUE files.
The MDS/MDF format *can* contain audio tracks, and DiskGui *can* mount images in that format... but it seems to ignore the audio tracks. Most likely DiskGui doesn't support audio tracks.
So there are two formats which support audio tracks, but neither of them are (fully) supported by DiskGui. Maybe someone should suggest this to the author of DiskGui...?