Major Bug with Selection Follows Playhead

I'm currently editing my first ever project on V14.1 of Resolve. I'm coming from Premiere as I gave up with all the bugs and sluggish performance. So far, so good for Resolve but with one major problem I've come across.

When activating Selection Follows Playhead, playback begins to stutter and drop probably 1/2 of all frames. This is on a simple one track 1080p timeline. No audio (other than from camera), no additional tracks whatsoever, no effects, no transitions. If I disable Selection Follows Playhead, playback returns to buttery smooth.

Anyone come across this or know whether it's been fixed?

Cheers

Shame to still see this problem lingering with all beta versions of Resolve 15, as well as the past 14.X release. Any sign of a fix?

[Peter Chamberlain]

No one can help as you haven’t provided the basic information about your system, config, OS etc.
Please review the post at the to of the forum “Before you post”

On Windows, I've noted a bit of a stutter in the Edit page GUI when "selection follows playhead" is active, but that stutter is not seen in either cinema view or external monitoring. And the indicator is showing real-time playback in all cases.

If your system is marginal, it might be more consequential(?)

[Shrinivas Ramani]

An alternative may be to try using Shift-V while playing back to select clip/edit under the playhead. While this is a more hands-on approach to selecting the clip being played back, it helps avoid rapid refreshes when playing back over very small cuts.

My system is as follows:
1. 8-core 16-thread Xeon Processor 2.4ghz
2. 32GB ram
3. GTX 1070 Graphics Card
4. 2 x SSD (one for system)
5. 8 x 3.5" drives for media storage
6. Windows 10 Pro 64-bit Version 10.0.16299 Build 16299

The performance hit when selecting "Selection follows playhead" is also occurring in all beta versions of Resolve 15.

[Peter Chamberlain]

Do you have only one UI monitor and it’s connected to the 1070?
Can you test with ProRes source clips, like ProRes HQ.

Just one monitor (4K 8 bit). I have no ProRes clips as I don't shoot in that format and not ideal for PC use.

Odd, I'm not seeing it at all now. Not on Prores or h.264 material.

You didn't note the file type you're editing. If it's GOP footage, you might want to transcode to DNxHR or another intra-frame format, if that's not too obvious.

All footage I've thrown at it has the same problem, this mainly consists of 1080p 8/10 bit varieties recorded in MP4 from the Panasonic GH5, with some 4K thrown in for good measure. I shoot in PAL 25 frames a second (sometimes 50p).

Just to reiterate though, all material plays absolutely fine in the timeline (including 4K files) but only with "Selection follows playhead" disabled. As all that function is doing is highlighting the clip under the playhead, it must be a bug as it goes from buttery smooth to unwatchable. However, the Frames Per Second indicator doesn't drop in line with what is actually happening on screen (e.g. it will show it's playing back at 25 frames per second where in reality it could be only 1 or 2 frames per second - certainly no higher than about 12 frames per second).

Tried with DNxHD. A bit smoother until you add a Transform. Then it's back to a very jerky playback. Frame count does not drop.

I am having this issue on 16.2.2, in a UHD/23.98 timeline with Alexa Mini LF ProRes 4444 footage. Specifically, the playhead stutters immediately going in and coming out of simple Cross Dissolve transitions in the timeline.

Disabling Selection Follows Playhead "fixes" the issue, although I don't consider that a fix, because I like to work with that option enabled at all times.

I am having this issue on 16.2.2, in a UHD/23.98 timeline with Alexa Mini LF ProRes 4444 footage. Specifically, the playhead stutters immediately going in and coming out of simple Cross Dissolve transitions in the timeline.

I think multiple streams of 4K ProRes 4444 will be taxing on an 8-year-old Mac Pro, even one with a big GPU and lots of RAM. My suggestion would be to do the session in HD and/or use the render cache for the transitions, and that should solve the problem. You can still render out in 4K at the very end of the session.

I bet using a very recent-vintage machine with a very powerful CPU and GPU will solve the problem.

I am having this issue on 16.2.2, in a UHD/23.98 timeline with Alexa Mini LF ProRes 4444 footage. Specifically, the playhead stutters immediately going in and coming out of simple Cross Dissolve transitions in the timeline.

I think multiple streams of 4K ProRes 4444 will be taxing on an 8-year-old Mac Pro, even one with a big GPU and lots of RAM. My suggestion would be to do the session in HD and/or use the render cache for the transitions, and that should solve the problem. You can still render out in 4K at the very end of the session.

I bet using a very recent-vintage machine with a very powerful CPU and GPU will solve the problem.

The issue occurs with a simple single-track, cuts only sequence, even with 1/4 Proxy Playback and Performance Mode totally enabled, cached User Mode transitions and with NO grade applied to the clips. Turning off "Selection Follows Playhead" alleviates the issue.

This is clearly a bug.

The issue occurs with a simple single-track, cuts only sequence, even with 1/4 Proxy Playback and Performance Mode totally enabled, cached User Mode transitions and with NO grade applied to the clips. Turning off "Selection Follows Playhead" alleviates the issue.

OK. What happens if Render Cache is turned on?

The issue occurs with a simple single-track, cuts only sequence, even with 1/4 Proxy Playback and Performance Mode totally enabled, cached User Mode transitions and with NO grade applied to the clips. Turning off "Selection Follows Playhead" alleviates the issue.

OK. What happens if Render Cache is turned on?

Render cache has no effect, as already mentioned.