... it appears that PC version 5.3.6.7 is the solution.
Background: after the latest iOS app update (2.00.31) I began having odd alert clip viewing issues. I have 6 cameras. No matter which camera alert window you chose, BI would bring up the latest alert - whether from that camera or not. Even if you brought up the live camera view and swept up, it would bring up the latest alert irregardless of the camera you were on. Plus, the alert window would cycle through all alerts if you arrowed backwards. Extremely annoying.
Things I tried:
Deleted all groups
Restarted PC app
Rebuilt database
Wiped iOS app, reinstalled (problem was happening on 4 devices though)
Swore
Cursed
Held breath
FINALLY, I tried going to the latest PC version even though I was already on the most stable release. Problem immediately disappeared. So FYI for anyone.