Why doesn't this sort by track, too?

%artist%%album%%track%

I have my Artist field sorting customized with that argument. While it does sort groups by Artist and Album, it often ignores the track order. Why is that, and how can I fix it?

Thank you!!!

could it be that some tracks are already sorted by the artist and album criteria as there are minute differences in the spelling?
Check it by selecting all tracks in that list which does not sort and which should have the same artist and album.
If the displays for artist and/or album in the tag panel switch to "keep" there are at least two different spellings which then invoke the sorting you see.

This question is already answered there ...
Sort by file name then by track number

DD.20101113.1805.CET