DoS flood settings on a Sophos XGS can look like packet loss in odd places. Streaming stutters, online games lag, and a speed test that should sit near 1 Gbps can fall to about 60 Mbps once protection starts biting.
I have also seen YouTube playback lose thousands of packets. That sort of drop is hard to ignore when the rest of the connection looks fine.
Symptoms of packet drops
Packet drops show up as choppy video, interrupted games, error messages, and long load times. If the connection keeps kicking you out or video keeps stuttering, something in the path is dropping traffic.
Speed tests are the clearest check. If throughput falls away when DoS settings are enabled, that points straight at the firewall configuration.
Streaming can degrade in the same way. Buffering and lag are often the first signs.
Where it happens
The problem is not always the hardware itself. The rest of the home network can contribute too.
Check the devices in the path and the wider setup. One bottleneck can make the whole connection look worse than it is.
If only certain devices are affected, that usually points to a device-specific limit or a configuration issue on that side.
Find the cause
Look at the DoS flood settings on the Sophos XGS first. For home use, they can be too sensitive and start dropping traffic that should pass cleanly.
Firmware matters too. Older releases may not behave well with current traffic patterns. It is also worth checking that the hardware can handle the speed you are paying for.
Traffic logs during a speed test can show the pattern. If the drops line up with a spike, that gives you something concrete to work with.
Adjusting DoS settings
Start by lowering the flood sensitivity. Test after each change so you can see what actually moves the needle.
Keep an eye on the drop logs. If traffic still gets dropped, go back and adjust again.
It is also worth turning DoS protection off temporarily to compare behaviour. If the problem disappears, you have at least narrowed it down.
After each change, run the same checks again.
Re-running speed tests
Run the speed test again and compare the result. If it climbs back towards the expected 1 Gbps, the settings change is probably doing the job.
Watch streaming too. Less buffering and less stutter is the other clue.
Long-term monitoring strategies
Keep checking the logs and the connection over time. These settings can drift back into trouble if you stop looking at them.
A few careful checks are usually enough to spot whether the firewall is the problem or whether something else in the network needs fixing.
