Hey Frank,

Indeed, our machines are quite different, which might limit the help I can give you. That said, I'm a little surprised OBS should cause that kind of CPU and fan spike just by opening OBS.

My initial thoughts is that OBS might not be configured or optimised to work with AMD GPUs on macOS. However, I've done a bit of Googling, and it seems OBS for Mac does support the AMD VCE encoder, so in theory you should get the results your are after.

I'd double-check your settings to make sure you've set your Stream/ Record encoder to your AMD hardware option. Check your Streamcam's setting too and make sure it's not sending a compressed video format to your Mac.

If that's set correctly, and you're still getting that CPU spike, I'd start looking clawing back some performance by disabling the preview, dropping your frame rate, canvas size, and dialling back any complexities in your capture (like browser sources or app windows).

You said you just want to record your Streamcam. If you're just recording the one source and aren't composing a scene, have you considered just recording via Quicktime?