I would recommend that you submit a system diagnostic, and call Sonos Support to discuss it. But don’t post the resulting diagnostic number here, they get sensitive about GDPR.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

I’m curious. What device or application is measuring this?

I have a Ubiquiti, when I run the topology there’s a feature you can enable the shows the flow of internet traffic to each device including its consumption.

Do those numbers concur with your internet usage report?  Because the Ubiquiti could be mistaking internal communications for internet usage.  Sonos devices are constantly speaking to each other, far far more than a normal device, but that shouldn’t show up as internet usage.  

That would not be true. I have 60 other devices that are showing normal usuage. Its a pipeline from my internet provider. Works as designed. The product is slowing down my internet speeds. When i unplug the product all returns to normal.

That’s fascinating. Do all of the other 60 devices cross communicate constantly, in the same way that Sonos devices do, in order to stay in sync?

What did Sonos support say, when you submitted the diagnostic, and called in? 

What is your ISP contract speed?

If you have Airtime Fairness turned on I suggest you turn it off. Sonos Beam maybe trying to match your other devices as a whole rather than individual units.

The Beam’s WiFi radio is 802.11n that has a theoretical maximum bandwidth (in Lab conditions) of 450Mb/s in 40Mhz 3x3 mode:

https://support.sonos.com/en-gb/article/supported-wifi-modes-and-security-standards-for-sonos-products

https://www.intel.com/content/www/us/en/support/articles/000005725/wireless/legacy-intel-wireless-products.html

Best practice is to use 20Mhz for 2.4 WiFi, so I assume max would be 144Mb/s in your network.

Either UniFi is mis calculating the reading, or maybe its the usage over time, not real time usage?

Please post a screen shot.