Has anyone else experienced this issue with Cycles? I’m not sure higher sampling gets rid of it and it may have something to do with the de-noise pass as it seems to appear after that.
If you are using the denoiser then try disabling “Glossy: Direct” in the Denoising panel settings.
You could also use a “clamp” value in the render tab (maybe 2 or 3) – but that may get rid of the highlights all together, which is something you probably don’t want.
I’ve had it, but only occasionally. Dunno what causes it, but I eventually went with high samples and no de-noising. A solution without clamping would be nice.
I guess for still images I can render with de-noise, and then do box selection render around problem area with higher samples and no de-noise and patch together in post. Thanks for the tips about clamp values.
In this case your solution of disabling Glossy Direct worked.