Cable Modem keeps dropping out [Solved]
 

I stumbled across this problem and solution but didn't see anything posted about it on Google, so I post it hoping it'll help someone else.

So I replaced my old cable modem after it's Ethernet port stopped working. New modem should make everything better, right? Nope. The new modem sync'd up and showed near-perfect signal levels & stats. BUT the modem would lose sync and reboot itself every 7-15 minutes.

Solution: I moved the cable modem 6 feet away from the router. 6+ hours now without a single error in the logs, no reboots, no dropouts, no packet loss.

It looks like the RF shielding in the modem is minimal and not good enough to handle the RF emitted by the router. I had decided to rearrange the equipment rack when I was changing modems and that's when I moved the new modem next to the router.

I'm glad you were able to work around your problem, but ...

You might want to list brand/model number of cable modem and router as it's certainly not a generic issue. Did you also switch the ethernet cable when you moved it apart?

-David

Um, if the RF shielding in the modem was inadequate, wouldn't it be inadequate starting at T+0, and not go magically inadequate at T+7 to T+15? :confused:

Perhaps the router is doing something every 7 to 15 minutes that causes emissions on a frequency that the modem's sensitive to?

I had the problem with a Motorola/Arris SB6141. Also seeing it with my replacement TP-Link modem as well.

Router's an ASUS RT-N66U + have a Ubiquiti Nanostation handling the WiFi traffic.

WOW, you shouldn't have to do that, either the one device has improper RF output and should be replaced, or the other doesn't have proper RF shielding and should be replaced. Manufacturing guidelines are very clear on what a device should be able to handle and what it can put out for single/noise. You don't have a good situation there and should replace the offending equipment or you are just going to have continued issues down the road.

Is the nanostation and antenna right next to it too? I bet that's the source of the interference .. but just a guess on my part. The cable modem and router are both very popular models, aren't they?

-David

I thought the NanoStation was an AirMax (not 802.11n/ac) device. How do you use it as a wireless AP? And why the NanoStation instead of a regular Unifi AP?