Router Randomly Limiting LAN to 100M/Full. Wifi Works normally

[ijholmes]

So I havent used my computer in maybe 2 days, everything worked perfectly fine, i didnt update anything regarding the router, there was a windows update I did last time I tunred the computer off, but outside of that, nothing has changed. 

However now my speeds are stuck at 100 when I check the stats manager. Its not my computer because when I run straight from my modem I get full speeds. Its just the router for some reason. All the Lan ports connected are showing 100M Full. all the connnected wifi devices are running at normal speeds (2-500) my internet is a 900 package. Tried factory reset already, nothing. Maybe the router has just bugged itself out and gone bad?

I have a R6220

[FURRYe38]

You'll need to check your PC. If nothing changed on the router and only change was the PC, then you need to check the PC. Be sure the ethernet adapter drivers are updated. Ensure you have a supporting ethernet adapter that supports 1000Mpbs connection rates. 

Be sure your using good quality LAN cable. CAT6 is recommended. 

Try a different wired PC or laptop

[ijholmes]

shouldnt be the PC because when I go to from the modem to the PC directly I get full speeds. Also its more so the modem because its limiting ALL of my Lan ports to 100 automatically, doesn't make sense for it to just randomly at the same time do that coming from the PC. 

[FURRYe38]

Has a power off then back ON with the ISP modem and router been performed? Pull the power adapters for the modem and router then back in after one minute
Be sure to restart your network in this sequence:
Turn off and unplug modem.
Turn off router and computers.
Turn on the router and wait 2 minutes for it to connect.
Turn on computers and rest of network.

What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?
Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 

[michaelkenward]

---

@ijholmes wrote:

shouldnt be the PC because when I go to from the modem to the PC directly I get full speeds.

---

What is that modem?

Just to rule out possible issues.

[ijholmes]

done all of this, forgot to note im an IT professional (Sys Engineer) and i've done all basic and obvious steps in a situation like this. looking for some more advanced possibilities as this has me stumped.