(Although it might well prove to be pointless, I'm still having fun with this - via DVD based tests now eh...

)
A question was raised (
here) about the 5680 dash .wav's and so far as I could tell, the 5680 dash
only gets its .wav's from within the C:/Audio directory tree ... I had them placed everywhere it might reasonably look for them on the DVD and renamed C:/Audio ... silence resulted (as per the 4920 dash) eh!
Additionally, I confirmed the 5680 dash doesn't run at all when two of the .wav's were renamed to eack other (whereas the 4920 didn't seem to care about that). However, if individual .wav's were renamed 5680 didn't mind (so if they're present in C:/Audio it pre-validates them, otherwise it's not concerned) eh.
Interestingly, there seemed to be 3 more .wav's in 4920 than there are in the 5680 manifest ... maybe they provide an opportunity for a potential wav hack (but since that would need to be via the C:\ drive, it's unlikely to be worthwhile anyone pursuing it) eh?