Choppy playback/editing despite using optimized media

Hi,
when I generate optmized media from iPhone footage (shot using Filmic Pro 4k 60fps h265) to DNxHR SQ quarter resolution and put it in the timeline Im still not getting smooth playback despite the fps indicator is all time green and doesnt seem to indicate any dropped frames.

My specs:
Davinci Resolve 16.2.1 (free version)
Ryzen 5 3600 6c/12t
16GB 3200MHz RAM
RTX 2070 8GB
1TB NVME SSD - for Windows & Resolve
2TB HDD - original footage, export location
1TB HDD - optimized media

First I thought that the HDD for optimized media is slow, but whole time I've got task manager open and HDD is under 30%, CPU arround 35% and GPU arround 20% load. I have the latest nvidia studio drivers installed.

I should also point out that the playback is fairly acceptable in the beginning but it is getting worse towards the end of the clip. CPU and GPU thermals are fine, no thermal throttling at all.

What am I doing wrong? Is this kind of behaviour normal for free version?

[Peter Chamberlain]

Please try 16.2.2

OK, so I updated Resolve to 16.2.2, but the problem remains the same. I even tried generating optimized media to other HDD and SSD (if its not a problem of that particular drive) but there was no change, playback is still choppy.

One thing that has changed after updating to 16.2.2 is utilization of CPU and GPU, which is now arround 50%. RAM usage is sitting at 9.5 - 10GB. All other apps are closed in the background, so there is no unwanted background activity that may casue trouble. The only thing applied to the clip is basic rotation and zoom, no color correction at all.

What is your Timeline Resolution and Framerate? Also, what is your monitoring/preview Resolution?

Not gonna lie, those HDDs are setting off red flags.

In your situation, I'd put the optimized media on the NVMe drive to eliminate the HDDs as an issue.

Just make sure Resolve is set to use Optimize Media when available, and then see how it plays back with the cache on that drive.

Also, make sure that you also set your Render Cache to DNxHR SQ Quarter Resolution, if you're allowing Resolve to utilize automatic render caching. The default is Automatic (i.e. Same as Source) Resolution and Framerates with DNxHR HQ or HQX CODEC. If Resolve Render Caches, then I'm pretty sure it will use the Cache over the Optimized Media, adn if that cache is bottlenecking your CPU, GPU, or Storage... you will have playback performance issues.

Generally, I set Render Cache to Off (additionally for Fusion Stuff) in my Default Project Profile, that way I have the option to turn it on (on a project-by-project basis), but it isn't on by default for EVERYTHING.

I would definitely upgrade that second HDD to a SATA SSD, at least, though I'm not sure why you'd bother putting a 1TB NVMe in the system if you're going to offload that to a mechanical HDD. Games need SSD storage a lot less than video editing. 500GB SATA SSDs are really cheap, these days, and is likely to function just fine for you as a Resolve Media (i.e. Cache) Drive.

Second that, I wouldn't put optimized media on a spinning disk.

Thank you for your responses. Really appreciate that.

As I said in my previous comment, I already changed optimized media location to my SSD and regenerated them again. I didnt find any difference.

I already had optimized media enabled and set to DNxHR SQ Quarter Resolution in project settings. Render cache is set to none, when I turn it on, it is even more laggy.

I´m not trying to make complicated videos full of heavy color grade or fusion effects. I just want to cut, straighten clips, make simple color correction and sometimes add text and background music. Thats it.

Lately I was considering buying Studio version because I really like Resolve, but this problem puts me off.

Also my timeline resolution is set to 3840 x 2160 59.94fps and video monitoring to HD 1080p 59.94fps.
I realized now that I do have some clips in my media pool that are 60fps and some are 59.94fps. Do you think this could be a problem?

[Peter Chamberlain]

Can u generate logs and a NFO as listed i the FAQs so someone can review.

Have the same problem here.
It doesn't matter were you put the files: ssd, nvme or spinning disk, there is no smooth playback in timelime and the clips do not have any effects or filters!

Thank you, I was able to resolve this issue, just by buying brand new nvme ssd. But I still don´t undersatand how is that possible when I tried 3 different drives (HDD, SATA SSD and my system NVME SSD) and neither of them worked. Now that I bought another NVME SSD (for now only as an external drive) just for this purpose, the timeline feels pretty smooth.

Anyway, thank you for your answers, really appreciate your help.

i had the same issue. scrubbing the timeline was buttery smooth but playback had seconds of freezes while the playback indicator remained green. turning down the video monitoring bit depth from 10 to 8 bit did the trick. still confused tho. shouldn't happen with a 5900x RTX3060 and SN850 Nvme ?
timeline 1080p 25fps
optimized media 1080p DNxHR LB

Similar issue here. 1080 video @29.97 just on the source monitor, not even in the timeline (although just as bad on the timeline.) Freezes for about a second about every 5 seconds. Makes editing quite challenging. I play the exact same file on Windows Media Player and it plays back smoothly so it's definitely something going on with Resolve. CPU and RAM (both) are max 50%, typically much less. I've tried transcoding in Handbrake but that doesn't do anything. I just don't get it.

Feature request: A checkbox to play video smoothly. That's really the biggest issue I keep seeing with DR.