@NeilBintcliffe 

Model:X90

Firmware: 1.1.7 Build 20230323 Rel 74101

I am having the same issue. i have tried both the 1GB and 2.5 GB ports. The throughput never exceeds 100 mbs and i have 1Gig internet.

Can some from Tplink comment on this?

Thanks.

NeilBintcliffe wrote

Hi,

I am having a problem with my Deco M4 setup. The 1Gb ports will only pass 100mbps after the last update. I have checked all the cables & tried the setting QoS TO 1000mbps, turning UPNP, Sip off as another articulated has suggested but nothing. It was working fine before the update & all wired items ran at full internet speed that I was getting 350mbps.

any help would be greatly appreciated.

  @NeilBintcliffe 

Finally found the problem. It was a 1Gb switch splitter that needed powering down & resetting. After that full speed of the internet was achieved. 👍🏻