Hard to explain but I'll give it a go:
I import all my old CDs into intunes and I number them 1-540 etc.
I put the CD in the comments field.
I sort the comments field everything is great.
Then I make a master playlist with all songs in it.
I then click in master playlist that far left field, and that sorts the track numbers perfectly, 1 or 20, 2 of 20 etc.
This has been working great for first 540 CDs and then suddently the track nubmer sorting is not right.
When I sort for comments 517 is not between 516 and 518 as it should be but at the bottom of the pile under 540. thanks