Disabling camera results in enormous padding packets traffic

Hi,

we are exploring possible ways of disabling video camera and we are noticing pretty weird behavior.

When we disable simulcast track by replacing it with null (replaceTrack(null)), the browser starts sending enormous number of padding packets on the highest encoding. It basically tries to keep 1.5Mbps bitrate (that’s our max bitrate for the “high” layer) which results in ~600packets/s. For layers “low” and “medium”, number of packets is almost equal to 0.

When we disable normal track by replacing it with null, the behavior is much different as we don’t send any padding packets. We send exactly 1 packet/s.

When we disable simulcast track with the official API (via setting enabled property to false), the situation is similar but not the same as when we call replaceTrack(null). The browser generates ~600packets/s (~1.5Mbps) for high encoding but about 15 packet/s for medium and 15 packets/s for low.

When we disable normal track with the official API, the browser sends ~15packets/s.

Isn’t this a bug? I would expect that when I disable track with the official API, the browser won’t generate 1.5Mbps using padding packets. The same for replaceTrack(null).

I included sample plots where you can see that we send 600packet/s but only 1.5kbps of media as padding packets are not included in bytes_in_bits/s