It happens when I join my friends server and vice versa. Only when I hang a torch and knock it down can I see the blocks.
Why can't I see blocks when I mine?
I had this problem when the internet connection of a friend I was connecting to was not good enough. And when I got a new router and hadn't forwarded ports for Xbox Live yet. Does your 360 or the 360 of your friend say that there is a strict NAT when you execute the network test?
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