Odd Auth-control code behavior

[Eric]

When you move to a subcategory (from Category:Lastname, Firstname to Category:Lastname, Firstname/Performer or /Arranger on IMSLP , say...) any Authority Control information it receives from Wikipedia articles seems to get all mangled up, often in the same way so far the few times I've tried this. (Not mangled up exactly- it goes right again if you return to the main category page. Just odd when you're looking at the sub-Cat.) Might be just my computer.