Track ordering information should never exist in the title field, so I would think that it would always play in track number order. If the track numbers aren't filled in, I would suppose they'd play in FID order (i.e., the order the files landed onto the hard disk, which could in theory be random.).

I'll tag 'em & try again

Neither of those things has anything to do with the track title, I would hope that the track title is never used to determine order.

No, you're right, but if my playlist is created in filename order then that's the order it should be played in isn't it? (Used to be OK on my iPod)