found another possible solution for NAT issues on xbox one that may help people. Haven't had a chance to check it out for myself but I will as soon as I get home. Heres the post.
Router & Modem make/model: Dlink DGL-5500
Wired or wireless: Both (1 wired console, 1 wireless)
Multiple consoles on the same network (Yes/No): Yes
I'm not sure if the Xbox Team is already working on these issues but because of this I've set both console power modes to "Energy-Saving" until a patch can resolve this. If the console power mode is "Instant-on" the system will not register UPnP with my router giving me a "Strict" NAT type. This happens to both consoles. By switching to "Energy-Saving" the console properly registers UPnP with my router and displays a "Open" NAT type and party chat etc. works as expected on both consoles. I hope the Xbox Team will be able to release an update to make the console properly register with UPnP when using the "Instant-on" feature because I'd like to go back to those settings at some point. I've also tried powering the console on from "Energy-Saving" mode and then switching back to "Instant-on" but the next day when I turn the console on again it's back to strict
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"Energy-Saving" is the only way to ensure both consoles always have an "Open" NAT on initial boot.
I also verified that running the multiplayer test followed by holding the triggers and bumpers does set it back to open again but it's a hassle to do that each time so I'll have to stick with "Energy-Saving" for now.
Seems like Microsoft just needs to have the Xbox do whatever the multiplayer hold triggers test does in the background each time the console resumes from instant-on?
That was posted by a member on xbox.com