Windows 10 and GTX980m
Broken: (example: 2.78 62a6ed9)
Fireflies with Glossy Multiscatter GGX
1 Open the blenderfile
2 Render the file
Recently I noticed fireflies in my renders and wasn't sure where they came from as I used fairly high sample count (2048spp up to 8192spp), MIS, Filter Glossy 0.2 and had caustics turned off. I found that it's comming from high roughness values and glossy multiscatter ggx option. The fireflies do not appear with 'standard' GGX.
I am not sure if this is expected behavoir and hope it's a valid bugreport. When looking for informations I only found that multiscatter GGX tends to be noisier but nothing about fireflies.