Question Intermittent Speed Loss


Jan 22, 2015
I am paying for a fast internet speed in my home - I believe it is 1000 Mbps. My wireless computer on average has a download speed of 400 Mbps and an upload speed of 35 Mbps. About once every four days my speed will drop to anywhere from 10 Mbps to 50 Mbps and my upload will be less than 1 Mbps. This usually lasts about 30 - 60 minutes. This speed will affect everything in the house - including a computer wired to the modem/router (which I will just refer to as the "modem" from now on).

I teach a class online in the evenings and I would usually see this happen sometime between 6:30 and 8:00. This is not an everyday thing, these are just the time I see it happen - when it happens.

It can happen anytime of the day, any day of the week.

Comcast has tested everything they can think of and they are out of ideas. Even though they said my modem was good, they also replaced that. They say that the only way they can proceed from here would be if they happen to be in the house, when it happens, so that they could run tests at that time. Since the problem is intermittent, that is virtually impossible.

To their credit, Comcast escalated this problem and I have been treated as a high priority customer these last few weeks. Nonetheless, as I said, they are out of ideas. Does anyone have any suggestions? I am open to hearing anything, even if you think it something that they have already tried.

In case it matters, the modem is on it's own separate line - no splitter. The last time Comcast came out they ran a new line from the box outside the house straight into my house and connected the modem to that. The modem is sitting right next to a TV. It's in a family room area, which is just off a kitchen and has (in a closet) washer and dryer. I suggested to my Comcast tech that I could move the modem elsewhere in the house, but he said that this wouldn't help.

Some things that have changed: I was teaching one night a week from 6:30-9:00 from mid-March to late April and never once had this problem. This was a Wednesday night class and my current class is Monday and Wednesday. Because of other reasons, at some time during that time period - probably in the latter half, we changed our service to the 1000 Mbps service. Also, somewhere during the end of that period - or possibly after - we had the TV cable box replaced because it was faulty.

This is very frustrating. If anyone has any ideas, I am very open to hearing them.