This is beginning to sound mor and more like a kernel timout issue during boot. We had this before with an earlier kernel prior to 1.0, and my dual-disk system used to cause problems until Mike stretched timeouts somewhat. The "None" announcements for playlists in the main menu is an old friend of mine

Don't forget the kernel itself is in FLASH, and it is booted and ready far faster than a mechanical component like a disk. What surprises me is that there is no decent timeout mechanism in Linux for disks that spin up slowly; this shows how Linux has developed - it has been always assumed that the boot device is the disk itself, which will be up to speed before any bootloader for the kernel becomes active. I am not sure what software is being used for directory mounting (mount? mnt?) but it does seem to be pretty intolerant. Either that or the player itself is expecting a mounted partition when it starts, and doesn't like to get "I'm still waiting" messages back from the mnt/mount sysreq.

It would be interesting to see what disk models and combinations are present in machines showing these boot problems - I bet a number of them are dual-disk.