Bitrate Jumping All Over the Place + Dropped Frames During Stream

[ThirtyIR]

Just updated to OBS 28.0 today.

Was streaming to YouTube using RTMPS in 4K 60fps @ 20Mbps and was working great (99% of the time).

After the update, switched to YouTube HLS 4K 60fps @ 20Mbps with HDR (Color Format P010 instead of NV12 and Color Space Rec. 2100 (PQ) instead of Rec. 709) and now the encoder is HEVC instead of NVENC (new).

Image quality looks superb on stream but there are a couple of big issues during the stream:

1. Bitrate is set to 20Mbps CBR but it jumps all over the place during the stream - goes as low as 5Mbps all the way up to 37Mbps - it should be pegged at 20Mbps and that's what it was like before this update for buttery smooth streaming at 4K 60fps.
2. I also noticed thousands of dropped frames - up to 7% during my latest stream so there were intermittent stutters which leads to a bad streaming experience. This problem was barely present before the update - if at all I had dropped frames, they were < 50 after a couple of hours of streaming. Same settings (4K 60fps @ 20Mbps) - only difference is HLS vs. RTMPS, HEVC vs. NVENC (new), and Color Format & Space due to gaming in HDR as opposed to SDR.

How to fix this issue of Dropped Frames and Bitrate jumping all over the place?

I want a buttery smooth 4K 60fps @ 20Mbps streaming experience.

Here's an example of a stream with the latest OBS update and settings:

- YouTube

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

youtu.be

 

[JohnPee]

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