I popped in Call of Duty 2 today for the first time in a few years, having never played it before on my 2013 iMac. While configuring the settings in the game menu the mouse would freeze for a few seconds, and then respond again to my movement, then freeze again, etc. Once in the single player game, the same thing happened. The game would freeze for a few seconds at a time on a very regular basis. What could be causing this? Edit: I just noticed that the Call of Duty 2 on the App Store is 1.3.1, and I have version 1.3, which is the latest that the game can be updated to when installed from the disc. Am I to assume that in order to work properly I need to buy the App again from Apple? This is looking very, very crooked.