Router/modem issues or something wrong with Xbox speedtest?

I have been tearing my hair out for the past three weeks trying to figure out what my issue is. Here is what is happening.

Here is how everything is setup at the moment;

Modem to Netgear X4S wired to Xbox One and PC

Modem to Netgear X4S wireless to two iphones, Xbox One S, PS4, and Nintendo.

I get 134 mbps download speed and 5 mbps upload speed max whether wired or wireless from everything except my Xbox One and One S. At first I thought I was having a router issue since I upgraded to the X4S so I contacted Netgear and they shipped me a new
one. Once the new one came in I hooked everything back up and I still had the same issue. Now I am thinking it's the modem. So I wire the modem directly to my PC and run a speed test and it is perfect 134 mbps download, 5 mbps upload as usual. I then wire
the modem directly to the Xbox...less than 50 mbps download with 5 mbps upload still. Just to be sure I go to my ISP and swap out the modem. The new modem that I received (Technicolor or Cisco) does the exact same thing when wired to the Xbox. Now I am
thinking that the Xbox One's ethernet port is messed up. So I hook it up to the wireless 5G and STILL only get less then 50 mbps when the router sits right next to the XBox. To investigate even further I bring my Xbox One S up and run a speedtest while wired
and on wireless 5G. Even the Xbox One S only gets 50mbps download max. I have port-forwarded and setup a static IP address to the Original Xbox One that I started doing my tests on and that didn't help the issue. To clarify further everything that is hooked
up to my router whether wired or wireless is running at 100+ mbps download speed except for the Xbox One's. Is there some kind of compatibility issue with either my modem or X4S router to the Xbox's? I didn't have this issue before when I had a Netgear N600.
I got rid of it because the wireless range wasn't very good. Any help at all is much appreciated.

:)

 

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