I've been running a speed test (speedtest.net) for the past few weeks. It shows that our upload speed is always less than 1 Mbps. I tried from multiple devices, from multiple jacks around the house and went directly from a laptop to the modem (no wifi router). Also reset the modem several times and had Xfinity reset it remotely several times.
An Xfinity technician visited and said that all looks ok outside the house. He ran a speed test in the house on his own device and also saw the upload is less than 1 Mbps but could not find a reason, so he just left and said they can't do anything about it right now.
This slow speed is causing lots of timeouts and other connectivity problems. I'm trying to work at home but I might be forced to go to an office 20 miles away.
Do you think it might be related to the amplifier in the box outside? Anything else to try to troubleshoot this? Obviously, Xfinity is not going to help right now.
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Thanks EG. Here are my modem's stats. But the Xfinity technician used his own device to test our connectivity and speeds (independent of our modem) and agreed that we are barely functional, especially with upload speeds. Do you see anything abnormal about these stats? Thanks.
|Frequency start Value|
|This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.|
|<tabindex=-1>Downstream Bonded Channels</tabindex=-1>|
|<tabindex=-1>Upstream Bonded Channels</tabindex=-1>|
|<tabindex=-1>Downstream OFDM Channels</tabindex=-1>|
|<tabindex=-1>Upstream OFDMA Channels</tabindex=-1>|
|Current System Time: Sat Apr 25 11:07:34 2020|
|System Up Time: 7:12:06|
Yep. The stats are o/k. We've been seeing a lot of posts here lately about speed issues. I suspect that it may have something to do with capacity / traffic congestion problems due to everyone being home on the internet.
Here's some of our recent speedtest results. Ping, download and upload. Note that we're on one of Xfinity's highest speed plans. And a technician visited and didn't fix anything. So, I'm hoping someone on this forum has some answers. One question I have is whether I can test the modem from the cable feed that comes into the box outside our house? Is that technically possible?
It's not just a speed issue, though. My son had a college exam yesterday and he was required to upload several 20 MB files but they all timed-out, to various websites (office.com, Google Drive, etc.). So we can't even send files that I was able to send through a dial-up modem 15 years ago?
I connected my Netgear CM1000 cable modem directly to the cable feed (outside the house) and the speed test jumped from an average 0.2 Mbps in the house to over 14 Mbps - consistently over several minutes.
So, my guess now is that the Commscope splitter/amplier Comcast installed is faulty, another device in our house is causing noise and/or the voltage to the amplier is not consistent.
I don't really have the time nor expertise to self-diagnose all of these things -- and I'm paying over $200 per month to Comcast for their "service" -- but after two technicians have been here and left without fixing anything, I really don't have any other choice but to try to fix it myself.
Next steps: Pull all cables from the splitter except to the cable modem upstairs and check the voltage to the amplier. I will also probably order a new splitter in case the one we have is causing the problems.
I replaced the splitter that Xfinity provided, made by Commscope, with an Arris amplifier/splitter and this resolved the issue. We're now getting about 15 Mbps upload speeds, up from the usual 0.1.
What I don't understand is why, after two technicians visited the house, after about six online chat sessions and several emails and phone calls, not once did an Xfinity rep mention the splitter as a possible reason for the problem. I can't tell you how many modem resets Xfinity did and asked me to do, and the upload speed remained under 1.0 Mbps, but that's all everyone recommended. There has to be an explanation for this.
My theory on the bad Commscope splitter is that it started failing due to moisture. An Xfinity technician who visited about eight months ago said he was not able to close the cable box all the way because the splitter was too big, so he zip-tied the box closed, leaving a 1/2-inch gap at the top. I live in the Pacific Northwest, where it rains a lot, and so plenty of rain made its way into the box. The second technician left the box the same way but added weather protection to the cable endpoints. But the Commscope splitter was likely already damaged at that point.