Keep getting: "you have been disconnected from xbox live" message when wired

Hi guys, so here's my story:

since I upgraded my Xbox to the gears of war 4: Xbox One S console, ive been getting a problem where my connection will disconnect every once in a while. It will literally disconnect me for 3-5 seconds then come right back. Now heres the thing, it didn't
happen before when I had my Halo 5 xbox one edition and it only happens when
I'm wired. Ive called support, ive tried everything and I'm absolutely stumped. My ps4 is also wired on the same modem/router and it never disconnects. In fact, I havent noticed anything else disconnect other than my xbox one s while wired. When I'm wireless,
I have no problems. Its driving me crazy.

Here is what I tried.

- complete reset of console (not fixed)

- swapped Ethernet wire with ps4 one (not fixed)

- bought new Ethernet wires (not fixed)

- used different port of router (not fixed)

- called support, been sent a new console (not fixed)

- rebooted router/network (not fixed)

I'm seriously out of ideas. I also cannot update my router/modem because its a Bell modem/router (combined) and it will not let me update the FW. It updates automatically.

Any ideas.....im completely stumped. Thx.

:)

 

Consistant disconnection from Xbox live.

I keep getting disconnected from Xbox live during game play, the intervals are random I can play for 20 minutes one time and 5 the next, game makes no difference Call of Duty or battlefield3, as well if I'm watching a DVD through my 360 I'll see a message
appear saying I've just been disconnected from live.

My NAT is set to open

Hard wired to a Belkin f5d8233-4v3 router

I looked up port forwarding I currently have nothing in my virtual servers and when I try to add ports 53,80,88,1863 and 3074 (as per Port Forwarding's website) I keep getting a message that says "line 1 is incorrect".

Any help appreciated.

 

xbox live

i keep getting disconnected from xbox live it's been doing that for awhile can you help me please thank you

 

Update:

So ive tried with 4 different Xboxes now, 1 original xbox one (no issues) 2 xbox one S (problems with both) and 1 xbox one X (still problems) and it still happens!!! It seems to only work with the original fat xbox one. Doesn't happen with my ps4 that's
also wired. It seems to be an xbox compatibility issue with the new xbox one models (S and X) with the Bell modem called: Home Hub 2000. Home Hub 2000 - support, help and troubleshooting from Bell Internet

MS please fix this. I cannot use my Xboxes wired because of this compatibility issue with the modem.