I have two xbox series S both on wireless 5GHz one will speed test at 150mps while the...

Speed test while connected to 5Ghz is///ping 14ms, download 136.01Mbps, upload 16.31Mbps

As a side note the Xbox One is not compatible with 5Ghz wifi when using WPA2-PSK security. And while wired is always a possibility in some cases it may not be even the least bit practical. Go into your routers settings and add your XB1's MAC address and
give it a static IP. While in there increase the "lease time" on IP assignment. This might help. Better yet assign the XB1 an IP on the console outside of your routers DHCP range. If you only have one XB360 + XB1 port forward 3074 to the IP you just set.

Also note your wireless will run at the speed of the slowest device connected. So to test unhook EVERY other wireless device while testing to make sure it isn't part of the problem.

My NAT was reporting as opened, and both an internal speed-test and an external test (using the Xbox Remote Play test) showed acceptable speeds.

I updated my initial post with a potential resolution that's been working for 3-days now smoothly. My 5GHz network configuration may have been an issue.

Xbox one. and yeah Its on the 5ghz signal.

You will probably not be able to get a much faster wireless download speed on the console due to it only supporting the N standard WiFi and not the not the newer faster AC standard as on the Xbox One S.

Hi

Can you please confirm if this an Xbox One or an Xbox One S console? As the Xbox One S supports the AC wifi standard where the original one does not and this will make a big difference to your wireless download speeds on the console.

Also if you have not already done so make sure you connect your console using the 5Ghz frequency.