Intermittent internet outages

... intermittent connectivity issues ...

The downstream signals look OK, but the upstream has problems. At least 3 channels should be locked. Only 1 is, and the power level on that one is out of spec (too high).

Network connection problems like this are often due to poor coax connections or damaged coax cable, usually in or near your home. Running the cable through a surge protector, a defective splitter, or too many splitters can cause signal problems as well. If there is an amplifier in the line make sure it's getting power. 

If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you still need help, please post your Internet plan speed and the modem model number.

If you can't find the problem or you'd rather have Comcast take care of it and an employee does not respond to your message here, call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/. It's not likely they can fix the problem remotely. If not, insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit ($70-$100) unless you have their Service Protection Plan ( https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device or anything outside your home you shouldn't be charged.

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Hi there,

Was able to restart the modem and upstream appears to have 4 locked now, although it still seems out of spec. 

The Internet plan is 400 Mbps - speed test gets back range from 55 to 115 Mbps over wifi.

The device is a Motorola MG7550.

Appreciate the help, thanks!

... The Internet plan is 400 Mbps ... The device is a Motorola MG7550. ...

Although it's probably not the primary problem, be aware that the MG7550 is not approved for use with 400 Mbps service. https://www.xfinity.com/support/devices says it is approved for use with plan speeds "Up to 373 Mbps". Using an device not approved for the plan speed typically results in measured speeds well below the speed you're paying for.

As for the updated upstream signal values, the intermittent nature of the signals suggests, as stated, a coax cable connection problem. I'm not sure what to make of, once again, one channel being out-of-spec high. I would guess that it too is most likely due to a cable fault, but it might also be due to a defective transmit channel in the modem.

It would be best to either replace the modem with one rated for use with your plan speed, or lower your plan speed below the modem's approved limit. And, as above, if you can't find the cause of the out-of-spec/missing upstream channels you'll need to have a premise tech take a look at the problem.

Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.