Audio Glitches on some exports

I'm having issues with occasional glitches on exported files. These glitches are not part of the source material or editing issues, and I'm not using any VST plugins or similar (I do all my audio processing beforehand in Cubase, and then import the edited/processed audio into Resolve).

The glitches are short burst of "digital noise", and they don't occur at edit points or anything obvious like that. They are consistent in that if I do the same export again, they appear in the same place in the same file.

I can fix them by making cuts in silence in the audio a few seconds before and after, and moving the audio by (say) one frame later, and then it won't do it again. (This generally doesn't matter for most of what I do as it's not got video synched to a speaker on screen).

System Spec:
Windows 10
Intel(R) Core(TM) i9-9900KF CPU @ 3.60GHz 3.60 GHz
32.0 GB RAM
RTX 3060 Graphics Card
Presonus Studio 1824c Audio Interface

I can't find a specific way to reproduce this - it just appears to be something that happens sometimes but I can't see a pattern to it.

This is on Resolve 18.1.4 Build 9, but I've seen it on previous Resolve 18 versions.

Screenshot shows the glitched audio (top), and the fixed audio by moving that segment by 1 frame.

Glitched audio (top), fixed audio (bottom)

resolve audio.png (39.62 KiB) Viewed 1744 times

Are the artefacts present regardless of deliverable format and settings?

Is the deliverable output via the Deliver page or an alternate method (e.g. QuickExport or audio only file output)?

Are the artefacts present regardless of deliverable format and settings?

Yes - my usual output format is .MP4 with H264, but it's present in .MOV and H265 as well.

Changing the in/out range gets rid of the issue - I have to export the entire timeline in this case to get the error - if I only do a minute or so it doesn't happen, which is a bit annoying with this example as it's half an hour long!

Is the deliverable output via the Deliver page or an alternate method (e.g. QuickExport or audio only file output)?

Output is done via the deliver page.

I'm having issues with occasional glitches on exported files. These glitches are not part of the source material or editing issues, and I'm not using any VST plugins or similar (I do all my audio processing beforehand in Cubase, and then import the edited/processed audio into Resolve).

What is the audio source format?

What is the audio source format?

Imported audio is 44.1kHz 16-bit WAV, Interleaved Stereo

Similar behaviour with source media at 48k?

I have changed my workflow so that I always export 48k 16-bit audio for import into Resolve... and I'm still having the same issue. Had it twice this week, exactly the same as before, and fixed by moving the audio one frame to stop it.

In one case, the glitch happened during a longer section of audio (i.e. in the edit, the audio was a minute or so long), which I don't think I'd seen before - typically it's during short edits. Again, the fix was straightforward (razor before the glitch, move the offending section by 1 frame, re-export and check in an audio editor), but it's now adding an extra step to my workflow as I have to import the audio from any video exports to ensure there aren't any glitches in there when I make a tiny edit to another part of the same video.

I'm still seeing this issue, even when using audio media which is at 48k (which I do for everything I'm going to use in Resolve).

It happens reasonably often, and in today's case, it's in the middle of a long project where there was no audio edit anywhere near the glitch area. Two images are attached - one of the audio output...

Audio glitches in output video file.

resolve audio output issue.png (16.49 KiB) Viewed 1032 times

This shows the area in Resolve where the glitch happened - there are no audio edits happening here.

Edit area showing there are no edits here

resolve edit area.png (55 KiB) Viewed 1032 times

I've fixed it by making cuts in the silence either side of this phrase and moving it one frame, and re-exporting. This is always fixable, but it's becoming painful as this happens pretty regularly now, and I have to import the audio from every export into a DAW and check for level issues.

What happens if you try a different approach, Darren?

Leave Cubase out of it. Do all the work in Fairlight.

Hi Jim

Unfortunately a lot of my content is about working in Cubase, so not using it for the audio generation isn't really an option for me....

You didn't mention it, but you wouldn't happen to be using nested timelines?

Any improvement reducing the Render Speed preference on the File tab of the Deliver page?

You didn't mention it, but you wouldn't happen to be using nested timelines?

I am not using nested timelines.

Any improvement reducing the Render Speed preference on the File tab of the Deliver page?

I shall give that a try and report back.

Any improvement reducing the Render Speed preference on the File tab of the Deliver page?

That's a great suggestion, Reynaud. I must admit that I've never understood why the render speed setting can improve symptoms of encode corruption. It's as if there are buffer overruns if you try to push things too fast on a less powerful system, but that points to an encode pipeline issue, doesn't it?

Unfortunately a lot of my content is about working in Cubase, so not using it for the audio generation isn't really an option for me....

Hmmm.

My thinking was that Cubase was doing something when writing the file that Resolve just didn't like. That's why I suggested not using it's audio files.

Might still be worth testing audio generated elsewhere, as a baseline.

If it's only the Cubase files that this happens with, we have a thread to pull.

The problem with that is that it would mean completely changing my workflow, for a maybe 1 in 10 issue that I can't predict whether or not it's going to happen. I've had a couple of weeks recently without any issues, and thought an update to resolve had fixed it... but it hadn't. Another time I had 3 out of 12 exports in a project I was doing have issues.

There's no meaningful way for me to work and create output with a substitute workflow generated elsewhere - it'd mean totally changing the way I work and I'd still not be sure that it was a fix as it's not repeatable.

So, an update. I've had a project to day that exhibited the issue.

Changing the render speed to slower than maximum (I set it to 50) made no difference - identical glitching in the audio.

I created a project archive and transferred it to my macbook Pro (M1 Max) and imported and rendered it on there. No glitch present when doing that.