XB10 10Gb Port Speedtest slower than 1Gb Port

@XfinityRay​ I appreciate the guidance, however given I am getting significant speed differences from just changing ports on the XB10, not sure if the guidance matches what I have already tried.

We understand the fast port is giving you 75 Mbps vs the other ports at 1 Gig. We are just making sure your setup is correct before we dive deeper into the troubleshooting this, @startedwithasmi. The CAT 5 cables support 1 Gig speed so that is why we ask about the cable you are using and for you to check that your Mac meets the requirements. I want to check your account from here to ensure we have the XB10 modem listed properly on your account as that can also cause this problem. 

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Xfinity Ray that was a good suggestion to check how the XB10 is listed on the account. The configuration could be set up as non-FDX which would be a problem for the equipment. You should not be allowed to install our self install without First checking that the provisioning is for FDX.

Thank you for reaching out on our Xfinity Community Forums, did you need any assistance at this time?