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Upgraded to 1Gbps with Xfinity SB6 Modem/Router-STILL getting very low wifi speeds/disconnects

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Upgraded to 1Gbps with Xfinity SB6 Modem/Router-STILL getting very low wifi speeds/disconnects

While I wait for yet another Comcast tech to arrive to help me figure this issue out, I am hoping to get some help from this forum. 


I was on Xfinity Blast for a few years and had issues with Wifi speeds going from 200+ when speed tested down to 30. 3 years ago, I got rid of the combo modem/router from Xfinity and bought an Arris Surfboard DB6141 and coupled that with an Apple Time Capsule. It was a bit better, but eventually started dropping to very low speeds again for WiFi. With the constant complaints from my family about slow speeds, I decided to try out the 1Gbps speed that Xfinity now offers. The tech hooked it up with the Xfinity their new SB6 (an Arris product) that they use for 1Gbps. I originally had them set this up with a bridge to use my Apple Time Capsule (newest one, 802.11ac, dual band, capable for up to 1300Gbps), but after the tech left, my Wifi again dropped drastically in speed. I contacted Comcast and had them take off the bridge to my Time Capsule and decided to troubleshoot the problem using just their equipment. (I have posted the speed test taken with the Xfinity SB6 next to the router 15 minutes apart from my MacBook Pro quad 4 intel i7). A drop from 600 to 60 is unacceptable. 

 

I have, again, purchased my own modem and this time a different router as well (will use Time Capsule only as back up disk). My son plays Xbox, all 3 of my children have MacAirs and iPhones in use, as well as my Mac, iPad, iPhone and my husband working from home on his iPad and Mac. We need a router capable of covering a large home and basement. After some preliminary research, I purchased Netgear CM1000 DOCSIS 3.1 as well as an expensive ASUS RT-AC88U. I hope to play around with these after the tech leaves since they are always upset about people using their own equipment. 

 

Could anyone help me understand why this might be happening though? I get a strong 800-950 signal with ethernet (cat5 - also bought some cat7 to upgrade those just in case), but Wifi drops to ridiculously low speeds with either Time Capsule or X-SB6 routers. 

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Problem Solver

Re: Upgraded to 1Gbps with Xfinity SB6 Modem/Router-STILL getting very low wifi speeds/disconnects

Funny, your experience mirrors mine almost to the T.

 

My 2¢ here:

 

Simply put, Wi Fi will always be slower and less reliable than Ethernet because you're subject to outside electronic interference a lot more- putting the router next to a TV, or turning on a microwave or using a cordless phone, have been known to interfere with Wi-Fi. (Even the other way around - LG's UltraFine 5k display for Macs was known to have a bug that messed up the display if close to a Wi-Fi router). Each Wi-Fi channel (2.4 Ghz, and 5Ghz) is also capable of shouldering much lower loads than Ethernet can.  Plus with the Time Capsule on the network, if any backups happen, that will severely slow down the network traffic. 

 

Your new ASUS router will help immensely - it has Mu-MIMO, which helps expand the wireless bandwidth your home has, and has two 5 Ghz channels for Wi-Fi. Neither the Time Capsule (I have an AIrport Extreme 6th Generation, similar but without the hard drive), nor XB6 have these features. ASUS also has a smartphone app to help you manage the router. (I have an RT AC-68P)

 

I suspect you're using the Time Capsule to back up all the Macs on your network, so you can still use the Time Capsule as a backup drive, however IMO you're better off retiring the Time Capsule and getting a stand alone hard drive to connect to the ASUS router since it has built in Time Capsule, XBox and iTunes server support. Or better yet, a decent NAS drive like those from WD, Drovo or Synology, that will help alleviate the bandwidth congestion. 


"Sometimes the best way to learn something is by doing it wrong and looking at what you did." - Neil Gaiman
New Poster

Re: Upgraded to 1Gbps with Xfinity SB6 Modem/Router-STILL getting very low wifi speeds/disconnects

Thank you for the feedback darkangelic. I appreciate the 2¢. I will probably continue to use my Time Capsule as a back up simply because I just invested in a new one when my other one burned out. However, I do hope to have some success with the new router and new modem. The one thing the Comcast tech mentioned is that other houses who have open lines, such as and unused TV cable, can actually cause interference as well. He has contacted his supervisor asking for them to do a neighborhood sweep of each outside cable box to see if that might be the issue. It is clear there is inference going on he said based on my phone cutting out three times yesterday as well. (They use the new Xfinity modem/routers to take care of landline phones now too.) The sudden drops in Wifi from 600 to 60 just do not make sense given where the modem/router is placed. The tech agreed. 

 

While I wait around for the neighborhood sweep for interference on that end of things, I think I will see what my new modem and router can do in the mean time. 

Problem Solver

Re: Upgraded to 1Gbps with Xfinity SB6 Modem/Router-STILL getting very low wifi speeds/disconnects

I'm not sure the neighborhood is an issue since you stated your Ethernet connection is consistently high. But to be sure, it makes sense to eliminate other possibilities.

Best of luck to you!

"Sometimes the best way to learn something is by doing it wrong and looking at what you did." - Neil Gaiman
Official Employee

Re: Upgraded to 1Gbps with Xfinity SB6 Modem/Router-STILL getting very low wifi speeds/disconnects

Hey THLCB5,

 

I just wanted to follow up and see how your services have been working since the tech came out and since your new modem and router have been installed. Have there been any changes?