CM500 and Orbi RBK50 Slow Performance

[mikesw1975]

I have a Netgear CM500 modem connected to Orbi RBK50 router with one satellite connected to Xfinity Blast (75mbps theoretical download speed) service. Initially, the download performance was very close to the theoretical speed regardless of wired or wireless connectivity. After less than 6 months of Netgear usage, the download speeds on wired connections have reduced by nearly 50 percent (40mbps) and the wireless speed reduced by over 90 percent (2.95mbps). Comcast customer support has confirmed that they are seeing 75mbps to the modem. I've tried factory resetting all Netgear hardware as well as adjusting 2.4 and 5ghz bands on the Orbi but with no change in performance. Has anyone else seen this type of behavior?

[guzzijason]

Just to narrow down the possibilities, have you tried connecting directly to the cable modem and running the speed test again? (Note that you probably need to reboot the modem if you change the device connected to it).

Also:

• What Orbi firmware version do yo have installed?
• Are you testing with the Comcast speed test site (speedtest.xfinity.com)?

[mikesw1975]

Thanks for the response. I tested directly at the modem and got an amazing 108mbps download. Orbi router firmware is V2.0.0.74. and I am using speedtest.net for my test site.

[guzzijason]

OK, so your upstream is solid - that's good.
I would stick with that firmware for now as well, at least until this issue is sorted out.

If you power off the satellite completely and just test using the main router only, do you still get poor results? And are you aware of any changes at all to your config recently?

[mikesw1975]

No changes to config that I'm aware. And the wireless performance is pretty much the same with or without the satellite. 

[guzzijason]

Hmmm... and you've already done a factory reset. It could be a hardware issue of some sort. If you haven't already, I'd try replaing the ethernet cable between router and modem. Other than that, I'm afraid I'm running out of ideas of things to check. Otherwise, it might be time to start looking into a warranty claim - if you've had it less than 6 months, I believe you should be covered there. Wish I had some other ideas for you.