We are having similar issues. We upgraded our internet tier to 250MB and modem to the CGM4140 com, and have worse service. Modem is in the exact same location as previous modem and the exact same devices are connecting, yet we constantly get dropped from the network, have poor connection status and lag, and get MISERABLE speed tests. I'm testing at a top of 45MB download speed on every device in the house thats on WIFI.👿 The LAN speed tests great. Since absolutely nothing else in my house has changed, I can only conclude that the WIFI module in these fancy Xfi modems are junk; I refuse to spend $119 for 3 extenders when my previous "outdated" modem had no problem delivering faster, consistent, and more reliable WIFI from the exact same location to the exact same devices in my home on a slower internet tier of 150 MB.
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