I start up DayZ and click either "Play" or "Change Server" (Doesn't matter which one), once I've spawned in I can see my friends and the game world, everyone is moving around the game isn't frozen but all controls stop working. I can't move or look around, or hit "esc" to bring up the menu, all keyboard and mouse functions cease. The only way to solve the problem is to restart DayZ, and to do that you have to "ctrl+alt+del" and force closure since no in game controls respond.
Even when on a wait timer you won't be able to hit "esc" and view the menu. Controls work fine until the second you connect to a server.
This has been happening to me and many of my friends since the .48 update. It happens randomly, some nights it will happen only once or twice the whole night. Other times it can happen up to 8 times in a row, maybe more but I got frustrated and quit playing for a few hours 8. I play with a fairly large group of people and from what I've seen this is by no means isolated to me.