Final Cut Pro 11.0 24fps to 25fps Sync Issue

Eureka! Thank you, Matti, for your suggestion, that enabled me to find the cause of the problem.

It seems that the videos I export in native 24 fps from Da Vinci Resolve are out of sync when I place them on a 25 fps timeline in FCP. The problem does not occur with 24 fps videos I create with Final Cut Pro.

This problem had never occurred before, so I did not assume that Da Vinci Resolve could have to do with it.

A new version of Resolve has just been released a few days after the previous one, so perhaps the developer may have been alerted about this issue and has solved it.

But still, I am open for ideas and suggestions about this interesting quirk. Perhaps there is more than meets the eye.

It is a very straightforward .mov Prores file. Here is the Media info from QuickTime:

As I explained in my OP, I add this file on a FCP project where the frame rate is 25 fps rather than the original 24 fps and instead of synchronizing perfectly, there is a 20-frame offset.

Mind you, before you say that this is obvious because of the difference in frame rate, it is not, because the audio is also converted in its speed and if I perform the fix, the audio and video are perfectly synchronized. So there is indeed a sort of added sound or video gap at the beginning of the timeline (only there isn't one visible) that causes this problem.

And again, it only happens with FCP 11.0.

I use this software professionally, because I provide files to broadcasters, and this is the first time this issue appeared. I can always use DaVinci Resolve, and I have to for normalizing audio (a feature FCP does not have) but I always use FCP for frame rate conversions because, so far, it has always been the easiest and most reliable choice.

It is only one clip, the Prores file I gave the info about.

I am sorry but I do not install software I am unfamiliar with on a production machine. I am sure you understand.

The screenshot does not show anything odd, but if I run the clip, the audio has a delay of 20 frames (about one second). Therefore, as I explained in my OP, I have to add a gap at the beginning of the timeline, detach the audio and resync it by moving it back 20 frames.