I’m having an issue with MCC that I can reproduce on my Xbox 100% of the time.
Once I start up MCC and attempt to play multiplayer, I cannot switch to Call of Duty: Advanced Warfare and play multiplayer there. It will wait 2 minutes and tell me it could not connect. Quiting MCC through the home screen options first does not solve the issue. I actually have to do a hard reset on my XBox.