Improving Comcast modem signal

@chungjh yes my modem/router has the internal power supply. As for the grounding box, since I'm a dealer I don't promote it on this site, feel free to PM me.

Thanks. I don't have any noise now with 93% efficient speakers. No mater where I plug mine in the with an external PS it has a ground loop issue. The only piece of gear that does that. It's less than a year old. Great transfer speeds with Cat 8 from Cat 5. The GL eliminator shut the stupid thing right up. 

I've tried 3 of the neighbors PS too. Same thing. You should hear it with Klipsch 103s they will run you out of the room. Neighbors rig.. GL eliminator fixed it right up.

Thanks Ay..

Regards

I've used my own Arris modems with Comcast/Xfinity since 2014.  They work fine.  If there is a problem, Xfinity will say it's your modem every time.  So far, it's never been the modem - instead an Xfinity service problem that is solved on their end within some period of time.  If you need  tech onsite, they might charge for that.  I've spent $325 on 3 modems 7 years (I like to keep them up to date), so even with a tech charge, I would be many $$ ahead.  Currently using an SB8200.  No GL, no LPS.

The Internet and the router are digital signal things. Am I wrong to think they don't introduce noise into the bitstream?

Now if a power supply is near some analog device in your setup, the solution would seem to be putting some distance between them or a similar action.

We never had Comcast. On AT&T and now our superior local ISP, Sonic Fiber, I have used a cheap TP-Link Archer 8 modem. It works fine. AT&T requires its gateway device, so my router was behind it as an access point. Sonic lets customers connect their own router to its ONT gateway.

Comcast is a joke.

I have used Netgear  modems for years, and I can assure you the problem isn’t with them. Last year they, Yfinity, offered me gig speed, only to slow down my connection from about 550mbs to 270. Then they told me that even though they lied about their promise to us, the "package" we had was no longer available, so we’d have to switch to a more expensive plan and live with the slower internet speed. ps, I live in FL, your state may differ in what they allow the cable companies to do to their citizens.

Of course, having dealt with them for decades, I recorded all of my conversations with them, and at the end started to play the earlier promissory recordings back while I was talking with customer service. (An apparent code phrase for taking care of the livestock.)

We cut the cable cord, and they haven’t asked for their boxes back yet, and are charging us less than the price of our now correctly charged 250 speed.

So, how to slay these demons? First, they may insist they be involved with resetting your modem, but you can do that with your modem app or through terminal/web browser…. But you can also do it the best way: Disconnect the cable and all other connections to the router, including power. Depress the power button for 30 seconds with no power connected, doing a clean state reboot, then reconnect the modem and attach the power and turn it on, giving it a minute or so to reboot.

I have found that this always solves any problem that I am financially responsible for.

I hope this helps, regardless of brand.