Yea, all that NAT communication mess seems to only come up between only some people in the party. The ones involved simply need to leave the party then return and it should correct itself.
It's an issue on Sony's end with the PSN. I've encountered this error somewhat frequently, only to log right back into a party and everything work fine. This happens quite frequently and is very annoying. When things were all hectic last night with the PSN, it took me 5 attempts to talk to others in my party because of this error. I'm already in the DMZ on my router and all ports are open.
Again, nothing to do with actual NAT in any way. 100% a Sony problem.
Hope some of this stuff helps someone.


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