[Bug] Round Trip Export of FCP XML Stereo Become Mono

If you export a timeline using FCP 7 XML v5 and then import the timeline without making any changes, all the audio tracks that were stereo are now Mono tracks.

I discovered this bug while attempting to use Plural Eyes 4. In trying to debug the issue I discovered that exporting a timeline and immediately importing it has the problem ruling out Plural Eyes as the problem.

Steps to Reproduce

1. Open or create a timeline. Throw a video/audio track onto the timeline.
2. Go to the Fairlight page to confirm the tracks are stereo.
3. Go to File->Export->Export Timelines. Select "FCP 7 XML V5"
4. Go to File->Import->Timeline and pick the XML just created

Expected: All audio tracks are in stereo
Actual:All audio tracks are are just the one channel.

Selection the option "Import multi-channel audio tracks as linked groups" has no effect. Doesn't give two audio clips per video file as would be expected from a video file with stereo sound.

It's been this way since 16.0.0.060. Regardless of it always being this way, import of the XML should not strip the audio to Mono channels.

I'm not sure that audio exports in XML will work between edit software. You can export STEMS, but not mixes and pans and levels and all of that. It's dicey and inconsistent.

This isn't about exporting pans and other audio edits. No audio edits have been performed. The audio was a stereo track, still is a stereo track but the XML import only sees a single audio track instead of the stereo it should be.

I can confirm this issue when importing stereo audio tracks via FCP7 XML into Adobe Premiere. I have not had this issue in older versions of Resolve.

I can confirm this issue when importing stereo audio tracks via FCP7 XML into Adobe Premiere. I have not had this issue in older versions of Resolve.

You are saying this is something new in the most recent version of Resolve?

You are saying this is something new in the most recent version of Resolve?

Pretty sure it's always been this way bringing FCP7 XML into Resolve... I've not personally known it different but I may have just been unlucky. It's not something I've had to do often. Have never considered it a bug, just a level of interchange support with that format that isn't implemented.

RedGiant provides this video for Plural Eyes.

With Plural Eyes 4, you export a FCP 7 V5 XML, import it into Plural Eyes, and then export it back out for importing into Resolve. Seems odd they would suggest doing this only to have it strip out all stereo audio tracks leaving only one channel per clip when importing the footage back in. I would hope that at some point importing the XML worked. I have reached out to them with a support ticket.

Just on the off chance that you're not aware (or someone else reading)... it's very easy to fix. Just select all, right click and choose Clip Attributes, change it to stereo. Also, if necessary, click the track header and change track type to Stereo. Done.

I can confirm this issue when importing stereo audio tracks via FCP7 XML into Adobe Premiere. I have not had this issue in older versions of Resolve.

You are saying this is something new in the most recent version of Resolve?

I have done a lot of TV series grading using round trip workflows from Premiere to Resolve and back and I have never seen this issue before. I can't guarantee it wasn't always like this as I never originated an edit in Resolve.

Reducing the # of audio channels seems like it would greatly impact any roundtrip workflows. At a minimum it would require constantly fixing it per Andy's post.

I have tested Resolve 17 Build 39 (no point release) and 16.2.8.005. Both of which strip the audio for imported XML to mono.

Plural Eyes includes a feature specifically in their software that has the user export as a FCP 7 XML, import in to Plural Eyes for syncing and then bringing it back in to Resolve. I am still working with their support to figure out why they implemented Resolve this way when importing an FCP 7 XML strips all audio down to Mono tracks. Maxon (Plural Eyes support) is telling me that since Resolve fails to import its own FCP 7 XML, that its Resolve's responsibility to fix this but I am failing to find a version for which this used to work.

Peter's experience notwithstanding, if I remember correctly, legacy FCP never supported multichannel track types nor multichannel clip types, they were always presented and handled in the UI using one track per channel eg Stereo was handled as (linked) Dual Mono. I just had a look at a simple Resolve 17.4.2 timeline XML (xmeml) export and can't see any evidence that BMD are actively augmenting the original spec in any way to add multichannel track/clip support (unlike Adobe, who, w/ Premiere's XML export, define and use their own internal datatypes eg premiereChannelType), so it doesn't surprise me that multichannel tracks containing multichannel clips in Resolve are ending up as mono tracks containing mono clips when passed through a vanilla XML interchange.

All that said, is there any reason to be specifically using FCP 7 XML as an interchange with PluralEyes? Would it not be possible to use the more modern FCPXML format (assuming PluralEyes supports it)? I did a a quick test roundtripping a stereo clip in a stereo track using FCPXML v1.9 and that seems to work fine. Does PluralEyes support FCP X?

FCP 7 V5 xml is what Plural Eyes supports for roundtripping from both Premiere and Resolve. Sounds like Plural Eyes overlooked this implementation. As shown in the video they have a very specific import option that brings in an xml from Resolve and you must use FCP 7 V5 xml to do so. They see all the tracks as being stereo but Resolve of course doesn't bring it back.

FCP 7 V5 xml is what Plural Eyes supports for roundtripping from both Premiere and Resolve. As shown in the video they have a very specific import option that brings in an xml from Resolve and you must use FCP 7 V5 xml to do so.

Understood, Nicolas. Apologies, I don't have or use PluralEyes, so without any knowledge of the process I was just wondering out loud what the result might be if one simply ignored the Resolve specific steps, as laid out by PluralEyes, and pretended (as far as PluralEyes is concerned) that you're actually round-tripping from/to FCP X instead, ie pass and receive an FCPXML v1.9 interchange file. But as I say, I've no experience with the software so I've no idea if it even supports FCP X workflows, and even if it does there may be good reasons why it won't can't or work from/to Resolve. Just trying to think of things to try.

Thanks Andy. I played around with the software a bit more and all solutions to get Plural Eyes 4 to import into Resolve are broken to some degree.

1. If you first convert your timeline to Mono tracks, you can send this timeline to Plural Eyes and import it back. However, none of the tracks are linked at all upon return. This solution requires quite a bit of prep to get it into Plural Eyes and quite a bit of cleanup upon return.
2. Export the stereo tracks, then go through and fix them upon return. It may be possible to batch fix them all. You'd have to do video audio tracks potentially separately from standalone audio tracks.
3. Create the project in Plural Eyes from scratch, and export the Resolve file. This file results in broken audio tracks. They all appear red and offline. Debugging this I discovered that the timecode is all wrong for the stand alone sound files. Manually going in to the XML and fixing this will allow one to successfully import the file but this requires finding the correct time code for every stand alone sound clip and manually editing the file.

I'll be continuing to work with Plural Eyes to sort this out but in the meantime this solution is broken. I'll be continuing to use Plural Eyes 3.5 and AAF import/export as this solution works nicely and doesn't result in any issues. The stereo tracks are preserved correctly and requires no prep work. It does require having a copy of Plural Eyes 3.5 however.

Thanks Andy. I played around with the software a bit more and all solutions to get Plural Eyes 4 to import into Resolve are broken to some degree.

1. If you first convert your timeline to Mono tracks, you can send this timeline to Plural Eyes and import it back. However, none of the tracks are linked at all upon return. This solution requires quite a bit of prep to get it into Plural Eyes and quite a bit of cleanup upon return.
2. Export the stereo tracks, then go through and fix them upon return. It may be possible to batch fix them all. You'd have to do video audio tracks potentially separately from standalone audio tracks.
3. Create the project in Plural Eyes from scratch, and export the Resolve file. This file results in broken audio tracks. They all appear red and offline. Debugging this I discovered that the timecode is all wrong for the stand alone sound files. Manually going in to the XML and fixing this will allow one to successfully import the file but this requires finding the correct time code for every stand alone sound clip and manually editing the file.

I'll be continuing to work with Plural Eyes to sort this out but in the meantime this solution is broken. I'll be continuing to use Plural Eyes 3.5 and AAF import/export as this solution works nicely and doesn't result in any issues. The stereo tracks are preserved correctly and requires no prep work. It does require having a copy of Plural Eyes 3.5 however.

Did you maybe find a fix for this problem?

Not yet. I have been working with Plural Eyes support but been busy with other work so haven't had a chance to follow up.

Still using Plural Eyes 3.5.

Not yet. I have been working with Plural Eyes support but been busy with other work so haven't had a chance to follow up.

Still using Plural Eyes 3.5.

Sorry to bother you more... How is 3.5 version compared to 4? any drawbacks?

Just on the off chance that you're not aware (or someone else reading)... it's very easy to fix. Just select all, right click and choose Clip Attributes, change it to stereo. Also, if necessary, click the track header and change track type to Stereo. Done.

Ah. That is a easy work around. I didn't realize you could change it for all clips. Thank you.

Not yet. I have been working with Plural Eyes support but been busy with other work so haven't had a chance to follow up.

Still using Plural Eyes 3.5.

Sorry to bother you more... How is 3.5 version compared to 4? any drawbacks?

Here are the differences between 3.5 and 4.

Version 4 Pros

• Syncs faster
• Has an automatic mode for parsing out different cameras and audio recorders

Version 4 Cons

• When automatic mode doesn't work there's no good way to get it to separate out what is mixed other then rearranging your media on disk.

Version 3.5 Pros

• You explicitly set how many cameras and audio recorders you have. Via drag and drop or other means you can add content per item. No need to re-arrange your content on disk. If your device dumps all the content into one folder you don't need to separate it out.
• More control over manually syncing pairs of clips when they fail

Version 3.5 Cons

• Slower syncing
• Clunkier UI.

General Notes
The primary purpose of Plural Eyes is to sync content. In every software that I have tested it works by far the best and amazingly well.

Ever since the purchase by Red Giant and transfer to Maxon the UI has taken a horrible turn. Its clunky, awkward and removes control that may be needed when automatic modes don't work.

I have an old Roland R-26 multi-track recorder. It stores each recording in its own folder with files for each set of inputs. I copy the content straight from the recorder to an Audio folder on my machine. Plural Eyes 4 does not handle this very well. It cannot tell that this recorder has separate audio tracks that were recorded at exactly the same time. To use it with Plural Eyes 4 you have to manually separate the content.

Note: This is not an Issue with Resolve as you create the project in Resolve first saving you from having to use their UI to sort out which audio and video files make up each angle.

Resolve 18.1 makes some changes to AAF. It breaks Plural Eyes 3.5. When you import video files it shows error messages for video saying "Error: audio extraction failed" and adds a new audio track with the video files duplicated an errors saying "Error: unsupported format".

I started a separate thread for the issue.