Can't choose frame rate when synchronizing clip with audio

Howdy! I am on FCPX 10.4 and noticed that when I try to create a synchronized clip and choose a custom resolution, the only frame rate that appears is 30p. The footage was shot at 23.98 but the only frame rate available is 30p. This happens regardless of the resolution as long as it's under "custom". Am I missing something?

I'm getting this

But instead of "1080p HD" select" Custom. I'm only getting 30p.

Not me. I only get the frame rate of the video clip.

Then it might be a bug in FCPX when using Red footage because I triple checked in the inspector and the footage was shot at 23.98.

That is weird. My 23.98 RED footage uses the shot's frame rate.

Try the usual trashing prefs.

Already tried. Unfortunately no dice. Very weird.

Same issue (only framerate 30p) in a project in a library 10.3 updated to 10.4. But with news rushs imported after update there is no problem with framerate..

I'm currently getting this same issue, except with a different frame rate.

Source ProRes QT files are 25p at 1080x1920. When I try to sync clips, FCPX forces me to choose 23.98.
Same thing happens when trying to do a multicam clip. I was able to get a compound clip to stay 25fps, but only after making a 25fps project at that size and making the compound clip from the project, as opposed to from the browser.

None of this behavior happened with the clips that were 1920x1080 at 25fps.

I am still on 10.4. Does anyone know if this is resolved in later updates?

BambooMagic.

Did you record seperate audio AND record to camera (dual system).

If you did, try not using the custom settings and just let FCP sync the audio to you camera audio (scratch) and you should be good. I noticed that the Sync section says it will sync according to frame rate of video clip.

These are merely pre-made quicktimes and wav files. FCPX will sync the audio and video -- it just forces everything into a 23.98 clip instead of leaving it all at their native 25fps. This introduces a judder to the video due to the conversion.

Only does this when using "Custom" for the resolution.
I sync'd everything swimingly into 25fps clips with the 1920x1080 material.