CM1200 Intermittent slow internet

[okfrontier]

Purchased this Netgear Nighthawk CM1200 on Amazon in June 2020. Started noticing intermittent "circle of death" while streaming TV shows using my Apple TV. I bought a new Nighthawk RAXE500 Router, thinking that would help fix the problem. The problem kept getting worse. Finally, it got so bad, all I got was intermittent 15 seconds of TV with 2 minutes of the circle of death. I called Cox, and they sent out a repairman. He started at the box outside and traced the signal all the way to the computer. The computer showed 150 mBPS, but the TV still had the circle of death. He suggested replacing the Netgear modem, which he did. Instantly that cleared up the problem!!! The Netgear Nighthawk CM1200 Modem lasted less than one year, and may have been bad from the very start, but I was too ignorant to know where the problem was coming from. I was blaming Cox fiber internet service for all the trouble for this whole past year, when it was the CM1200 all along!!! Since it is out of warranty, I am not sure if Netgear would repair this modem, if I pay them for the repairs, or if they even have a repair department? 

[FURRYe38]

Please post a copy and paste of the modems connection status page.
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
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. 
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Mod...
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

Connect 1 wired PC to the modem, with out the RAXE router in the mix and run some speed tests and video streams if possible on this PC while while connected to the CM modem. 

[okfrontier]

Cox replaced the Netgear modem with a rental modem. Would like to get the Netgear repaired if they will ever repair it since it is out of warranty??? 

[FURRYe38]

No sure if NG repairs modems. 
If out of warranty, you'll need to probably purchase a support contract to make contact with NG support. 

Just be cause they replaced the modem with theres doesn't mean the CM modem is entirely at fault. The questions presented would need to  be checked. Posting this information as well would be helpful. 

One thing you can try is to take the modem to a different location, say friend, family or nieghbor and see if the problem follows. 

Also need to check the power adapter as well for the CM modem. These can fail or go bad. 

[okfrontier]

Thanks for your suggestions, but Netgear wanted $89 for a 6 month service contract, and over $200 for a 2 year contract. I paid $200 for the modem to start, so I just returned the Cox rental modem and bought a Motorola MB8611 on Amazon which has same day delivery for $169. Going to give it a try, since the Netgear CM1200 lasted less than a year before it started to fail!!! 

[FURRYe38]

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