Choppy playback in Premiere Pro CC 2015.2

[Andy Lewis]

2-camera multicam: I get decent playback and then after 30 seconds or so CPU load ramps up to about 700% and playback chokes completely. From that point on the sound will play and the image will update about once per second. Playback at this point is similar to ‘software only’ mode. ie. unusably choppy.

Footage is 1080p xavc-s and xavc-l. Storage is a thunderbolt raid and computer is a 2015 retina i7 macbook pro with 16GB RAM. The fact that it will play ok for longer when cool suggests that overheating is involved but not sure if Premiere is the root of the problem or the victim of a hardware fault.

GPU is AMD Radeon R9 M370X 2048 MB. Maybe it’s throttling at high temperatures? Or maybe Premiere is going crazy and not using the GPU properly.

I’ve tried everything suggested above (some of them were new to me, thanks). Nothing seems to help though. Playback is better if I transcode to prores but it’s still not great.

Anyone having similar problems? It would be interesting if anyone is having similar problems on a different computer.