NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
CM1200 useless on Charter/Spectrum after they enabled OFDMA on upstream channels
Purchased a CM1200 modem a few months back to use with my spectrum service. Has been working fine for the last 3 months with OFDM on the downstream channels and regular upstream bonded channels. About 2 weeks ago spectrum switched my area to upstream OFDMA channels and immediately the modem became a brick. It syncs partial service for both DS and US. T3 timeout errors like crazy in the modem event log. Switch back to my trusty D3 arris SB6183 and all works fine again.
Realzing this was not a plant issue or local issue in my home after reading about other people having the same I went ahead an opened up an FCC complaint with spectrum to see what could be done. After troubleshooting a tech at spectrum and him escalating they basically said it was a netgear problem and to check with netgear on progress of a potential firmware update to be deployed for this modem.
Anyone know if netgear has a firmware update planned for this model? I would have just returned the damn thing but I am beyond my return window as the modem worked flawlessly for 3 months until OFDMA was turned on in my area.
Thanks
14 Replies
Additional photo with errors.
Factory reset already done and LAG is not in use.
Spectrum said netgear already knows about this issue and is working on a fix. trying to figure out the timing of the new firware release.
Well CC and XF ISP got v2 FW update this past month. I presume all the rest are forth coming. NG doesn't make it know when they will push to ISPs though. So you'll have to keep in contact with your ISP about this as they are the ones the can only update FW on modems.
Good Luck.
pls DM me
Any motion with this and Spectrum? I'll also DM you just in case there's something I can do or test... because this just recently started happening to me as well. Endless T3 and T4 timeouts, causing eventual connection instability/intermittency.
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.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
Draco wrote:Any motion with this and Spectrum? I'll also DM you just in case there's something I can do or test... because this just recently started happening to me as well. Endless T3 and T4 timeouts, causing eventual connection instability/intermittency.
