Comcast Internet issues

We ‘cut the cord’ and shifted from DirecTV to Internet streaming in 2019, and, like almost everyone else, I’ve been working from our home office since March 2020. A few months ago, we started to see buffering issues with the TV, and more recently reconnect/timeout issues with VPN connections and Teams calls. At first the cable modem looked OK, and I optimized our internal network (Meraki MX/Switch and Google Wi-Fi) because I hadn’t touched it in three years. No real improvement, so I purchased a new Motorola MB7621 cable modem because the SB6183 was five years old. No change, BUT I noticed the event logs were getting flooded with “T3 timeouts” (reference screen shots below).

I contacted Comcast support via chat, who realized this wasn’t a ‘reset your cable modem’ issue, and they gave me a link to schedule a call back. Fifteen minutes later, I was on the phone with Charles. He didn’t see any issues on his side, and I asked about connecting my old cable modem. We re-registered the old modem, and as soon as he did, he saw errors on the line. At that point, he scheduled a technician to come to the house.

The technician was very good. I showed him how the cable was routed to the house, and he tested the underground cable and determined it needed to be replaced. He also shifted the coax ground from the water pipe to the electric box as that’s the current best practice because newer homes are shifting from copper plumbing to PEX. With that in place, he tested the connection to the cable modem and found that was out of spec as well!

After replacing the connections end-to-end, I see ZERO errors on the cable modem, and with that no buffering, dropped connections, and faster transfers (OS downloads, for example).

Comcast gets beat up a lot, but my customer service experience was exceptional. Fingers crossed the follow-up is as good – they need to bury the temporary cable, but I’m sure it will be just as smooth.

MB7621 Error Logs

SB6183 Error Logs