Multi-channel audio from nested timelines summed to mono

Hi all

I'm using Resolve Studio 16.2.2.012 on macOS 10.14.6.

I'm trying to do a test where I have a nested timeline or compound clip that outputs multi-channel audio to the timeline it's on, such that the enclosing timeline can then access any of the audio tracks/channels in the nested timeline.

Every time I try, I get a weird situation where every audio track in the nested timeline is summed together, and copied to all the channels of the parent track.

Here's an example, shown in Fairlight.

Nested Timeline setup:


This timeline contains three video and three audio tracks. The three audio tracks are all mono. The Bus Format of the timeline is set to 5.1.

Parent timeline setup:


This timeline contains one video/audio track, which is the nested timeline. Its audio track is set to 5.1 format. Its Bus Format is set to 5.1, although I don't think this should matter.

What I expected to see was that the parent timeline would show three different channels of audio, each corresponding to the separate tracks of the nested timeline. Instead what I get is three identical channels, each of which is the mono sum of the three tracks from the nested timeline.

I'm using 5.1 bus format in these examples, but I've also tried Adaptive 3, and also plain stereo. The issue is the same in all formats.

After writing the above I tried quitting and reloading the program, and suddenly my parent timeline was correctly showing three different channels of audio, matching the three tracks in the nested timeline.

Then I tried changing the content of track 3 in the nested timeline, and the problem was immediately back. When it happened again it was just after I'd added a nested timeline to the nested timeline, so I don't know if that could be a factor. But since then I've tried removing the second nested timeline, quit Resolve and reloaded, and it's still broken.

This is really frustrating as I don't even know if I want to end up using multi-channel nested timelines; I was hoping to do a quick test to see if it would allow me faster editing using the multi-cam system. In the end I've spent 2 hours just trying to get it to work.

Any advice on what's going on and how to avoid it reoccurring would be much appreciated.

Since I first posted this, I've done some more experimenting.

I think the crux of the issue is that I didn't have the pan settings right in some of my tests. Eg if I had all three tracks panned to centre, then the parent timeline would see the same output in all channels of its Adaptive track?

However things were made much more complicated and confusing by the fact that I must have also hit one or more Resolve bugs, because I definitely tested pan settings multiple times, and it still didn't work. And then suddenly I got it working on one occasion simply by quitting and reloading Resolve.

I finally got to the point where I could reliably get a nested timeline to expose its X tracks to the parent timeline. However I then stopped, because I can't use it for what I hoped to use it for, because MultiCam clips are locked as Bus Format = Stereo. You can try changing the Bus Format of a MultiCam clip and it will let you, but as soon as you close and re-open it, it reverts to stereo. So I could find no way to get a MultiCam clip to pass multiple tracks of audio for a single camera angle. (I worked around this later by duplicating the angles with a MC clip, with different audio for each duplicated angle. A bit messy, but it works.)

I have to say I find the audio routing of Resolve to be rather confusing. I suppose it makes sense that a nested timeline acts basically as its own mixer, and thus pan settings affected the parent timeline, but it makes me think there really should be some way to expose the raw audio of a nested timeline/clip. Eg a Bus Format of "Pass-Through" or similar, which simply passes every track in the nested timeline through to the equivalent channel of the parent timeline.

Even better would be if nested timelines and compound clips could (optionally) add multiple tracks to their parent timelines, not just channels.

This is already possible with Media Clips: if a media clip has two or more tracks (eg in-camera + linked), this can result in more than one track being added to timelines that use them, and you can manipulate them individually. I would love if this were possible with nested timelines and compound clips as well.

We have the same problem, it is impossible to get Multi Channel Audio (for example Adaptive 5) to work in Multicam / Compound Clips or Nested Timelines.
The Nested /Compound / Multichannel Clip mostly only passes the first two stereo Tracks through, so as soon as we Mute Channel 1&2 inside the nested Timeline, the audio does not get passed through to the parent timeline.

This is rather frustrating and makes working with nested/Compound or Mulicam Clips impossible when having multi channel audio.

The biggest problem is that, sometimes it works, sometimes it doesn't and the reason seems to be rather random. We have spent hours trying to "fix it", from bus routing to panning to trying different channel formats... and sometimes got it to work only to have it break again a little later for an uncomprehensible reason.

Bug still there in DaVinci 17 beta.

Did you find any workarounds / solutions?

I'm having exactly the same problem, but with just simple Stereo L-R pans.
I'm working on a project that requires individual exports of various elements on my timeline, so I've used compound clips all over the place to group together things that need to be in a single file.

I've done this a lot before, but this is the first time I've done this in a project that has Left-Right panning and separation at its core. When I am inside the compound timeline, it all works perfectly. The moment I get out to the master timeline, everything is center-panned again.

It's extremely frustrating! There are way too many files for me to export each one separately at the compound timeline level!

I'm having similar issues in Studio 17.1.1. The audio seems to be stereo at least sometimes but it's waving between left and right, I get loud pops randomly, the main timeline is playing the audio at around -12dB volume. I have checked all the faders multiple times and there is no way I would have -12dB lurking somewhere. Most disturbingly all the issues are also rendered in export.

The pops are rendered totally nondeterministically. Also interestingly the loudness meter shows the same values in both timelines even though the channel meters and my ears can totally prove that the audio is almost silent.

Edit:

The pops are not actually artefacts but what is happening is that Resolve is repeatedly "echoing" some buffer from few seconds before the current time. When I keep jogging back and forth in the timeline I can make it play (and presumably render) a short clip from any earlier point of the timeline. It seems the buffer it keeps repeating on top of the current audio gets reused at some point and often starts repeating something else.

Similar issues here. Trying to understand how Fairlight fits into the audio routing between timelines.

We have a DME mix that I'm trying to get to work with a rough cut of a trailer (edited before the mix).

The only workaround I've found is to put the mix into the source timeline, remove the unmixed audio, decompose the audio only into the trailer timeline, then relink to the video clip of the nested timeline.

As with everything, I should have tested this out first. I mistakenly assumed that adaptive audio tracks and nested timelines would let me choose what tracks to use, like with linked audio.