When signing up multiple participants, the second contact's selections appear on the first contact's participant record

Steps to reproduce:

• Create an event
• On the Fees tab, select a price set with two questions (not sure if this is necessary or if the error can be reproduced with a quick config price set)
• Register multiple participants by settings "How many people are you registering?" > 1

The records for the second contact display correctly, but the primary contact shows selections for both users.