Massive Download Drop in Bufferbloat Test (220 Mbps → ~10 Mbps) on NetDuma R3

[Sergejs Kotovs]

Hi,

I’m experiencing a strange issue with my NetDuma R3 and wanted to check if others have the same problem.

When I run a normal speed test (e.g. Ookla Speedtest), I get my full speed:

• Download: ~220 Mbps
• Upload: ~40 Mbps

However, when I run the Waveform Bufferbloat Test:

• Upload looks normal
• BUT download drops massively to around 10 Mbps

This is a huge difference (more than 20x lower than expected).

[Netduma Fraser]

If speedtest.net is showing your normal speeds then the router isn't limiting you but try toggling speed test bypass in Ping Optimizer > Advanced. Otherwise it's unlikely there is any feature impacting it and is more likely the site.

[Sergejs Kotovs]

Yeah, Fraser, you were probably right. I checked this morning and everything’s fine. Yesterday it was messed up, now it’s normal. That site is just buggy as hell — screw that site.

[Sergejs Kotovs]

Here are my results today — 10:47 AM, April 21, 2026.
And the next day it looks like this… everything is kinda weird.