Recently I was configuring a Tomato router for QoS. I was confused to discover all the VoIP equipment started dropping registration. I checked the tracked connections and verified the VoIP traffic was correctly classified as High. That should have worked, but when I disabled QoS, they immediately re-registered.
The problem was that I had set the maximum speed for the High class to No Limit. On older builds of Tomato I've used, this exempted that class from throttling. This time I did not observe that behaviour.
I reset the maximum speed to 100% and now things are working properly. Instead of No Limit, now I use No Ingress QOS for UDP which is a setting not present in older builds. This seems to produce the same behaviour.
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