Hi all, I think I found a bug or hard limit in the ZenWifi ET12 router's QoS logic for Adaptive QoS. Not sure how to get this to the product team to look at it, but I have 2.5gbit AT&T fiber internet. Directly on my gateway device, I can exceed 2gbit upload and download. In the ET12 WebUI, I can get SpeedTest results nearing 2gbit (this is usually server-dependent - some SpeedTest servers are limited to 1gbit, but selecting a local AT&T server gives the expected speeds). But in the QoS tab, with Adaptive QoS enabled, and 2500/2500 set as total bandwidth, clients are unable to access more than 850-920 megabits per client, even when connected to the router on a 2.5gbit port or a 10gbit switch port. Selecting per-host QoS and setting over 2gbit, or disabling QoS entirely, immediately double the speedtest results on router client devices. I believe the Adaptive QoS may be internally limiting the max throughput to 1000mbit up & down, despite the WebUI setting being set to a higher number. If there's a way of getting this in front of an engineer, I'm happy to provide more info, diagnostics, config dump, etc.
