My friends and I (6 of us) have all played Survival Mode with each other and almost all of the time the game ends up going out of sync with the other player.  We will be playing normally and then at some point we are both just playing our own game!  The other person is still in the game but they are walking into walls and shooting nothing as they are controlling the character, but in their own parallel game (universe!).  As you can imagine, this really pi$$es you off when you get to level 28 or so and then this happens, forcing you to quit and restart.  I've wasted so much time on this.

We have no problems playing the Mission mode or multiplayer.

The problem is well documented by other players on the internet and has been happening since game launch.  Still no fix.  What's the deal Sledgehammer?

System specs:

ASUS G1-P7P55E with Thermaltake Toughpower XT 875W PSU

Intel Core i5-650 overclocked @ 3.36GHz with Akasa AK-CC017 Freedom Tower cooler

Corsair 8GB Dual Channel DDR3 1333MHz

MSI N560GTX-Ti Twin Frozr II/OC overclocked @900MHz

Crucial RealSSD C300 128GB SATA 6Gb/s (Windows 7 Home Premium)