CM700 compatibility with Xfinity 600mbps

[jortease]

Bought the CM700 modem to use for my Xfinity 300mbps speed plan. It works great, i get at least 300mbps wired directly to my own router. Recently i decided to increase my plan speed to 600mbps and now i'm running into slower than before speed issues. Getting at most 140-180mbps wired directly into my router. I was under the impression this modem would be able to support this plan speed as I have searched around and haven't found anything saying otherwise. Has anyone had the same experience with this modem and possibly not supporting the 600mbps speed plan from Xfinity? Need to know whether i should go back to my previous plan speed or find a new modem that supports this. 

[FURRYe38]

Be sure to power OFF the modem for 1 minute them back ON.

Be sure to have the ISP re-send the configuration file to the modem.

Have the ISP check the signal and line quality UP to the modem. 
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 

[Derrickh29]

I am having the same issue and there is a splitter there, I bet it is causing issues!

Why does it create issues and what would do in a similar situa?

[FURRYe38]

Be sure to power OFF the modem for 1 minute them back ON.

Be sure to have the ISP re-send the configuration file to the modem.

Have the ISP check the signal and line quality UP to the modem. 
Be sure there are no coax cable line splitters in the between the modem and ISP service box. Splitters can cause a reduction of line signal levels to the modem or induce noise on th line as well. 
Be sure your using good quality RG6 coax cable up to the modem. 

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@Derrickh29 wrote:
I am having the same issue and there is a splitter there, I bet it is causing issues!

Why does it create issues and what would do in a similar situa?

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