Sub-Summary Sort not working

[James Gill]

I have a many-to-many relationship that is not producing the sub-summary sort that I expect to see. Basically, I can add a portal viewing the relationship that I want to sort and I can see all of my related records. however, when I switch the layout to a list view and add a sub-summary section using the same relationship that worked in the portal, I can only see the first related record after I do my sort.

What gives? I've never had any problem with sub-summary sorts before but this is driving me up the wall.