Your speed test says 200 Mbps, but your video calls still stutter and games still lag. The culprit is often bufferbloat — oversized network buffers that add huge latency spikes when your connection gets busy.

It works like this: when you saturate your upload or download, packets queue up in bloated buffers instead of being dropped. That queue adds hundreds of milliseconds of delay — fine for downloads, terrible for anything real-time.

Testing is simple: measure your latency while idle, then again while saturating the connection with a download. If latency jumps from 20ms to 300ms+, you have bufferbloat.

The fix is Smart Queue Management (SQM) on your router, which keeps queues short and latency stable. Many modern routers include it — it is often one checkbox away.