M1 playback issues

I just purchased a new M1 Macbook Air after watching all of the raves on Youtube. My first 15 minutes fooling around showed excellent performance with 4k 10bit h.265 footage with a few nodes and lens correction. The timeline was snappy and playback was perfect at 29.97.

Then, like a switch it went to hell. Horrible stuttering and jumping from 12-40fps. Totally unusable. Not running any other apps, nothing different about the timeline or clips other than that they have been trimmed.

Any ideas?

Hello,

It sounds to me that the M1 may have been getting hot and throttling back. From my research it looks like the Macbook Air doesn't have a lot of cooling like some of the other mac models. Since you mentioned that it ran well for 15 minutes I suspect overheating.

Can you reproduce the problem? If you let the mac cool down and try again do you get the same ~15 minutes before trouble begins?

Good idea, but that isn't the problem. I rebooted the system fresh and cool this morning (though the laptop barely puts off any heat at all) and the playback issues persist.

Very frustrating. I'm running the 17.1 beta specifically for the M1 chips.

So this problem magically went away and the little Air is chewing through h.265 much more smoothly than my i7 w/32gigs of RAM.

I found a YouTube video where a FCP user had a similar thing happen when his Air was brand new and he chalked it up to background processes occurring during the first few hours of use. His guess is as good as mine, but I'm happy.

A similar issue occured to me on a 13-inch MacBook Pro M1 (8GB memory). I'm renting the device to test out its limits and to see whether an upcoming M1 16-inch might be worth the investment over an Intel/AMD-based 16-incher.

Out-of-box, with all updates installed and Resolve 17.1 beta 6, the M1 did just fine on a 1080p timeline, up to 60p. However, it struggled significantly at a 2160p timeline, even at 24p – no matter the codec of the source clips (I tested 10bit XAVC-S, ProRes 422HQ, ProRes4444 and r3d).

Then, I nuked the MacBook, wiping the drive and re-installing macOS afresh. After installing Resolve 17.1 beta 6 again, playback now only stutters during the first few frames with 2160p 60p footage, and is fairly smooth on anything lower resolution/framerate.

The 8GB of unified memory might be at least part of the culprit, however I didn't expect the M1 to struggle as hard as it did – even on clips without any grading or effects.