FCPX Reference Waveform audio levels, but no audio.

Hello. Running FCPX 10.0.8. Can not update as it is not my machine to update.

After importing media (Sony EX cameras I believe), some clips will have no audio, and others will. Opening the non audio producing files in VLC also says there is no audio. However, looking at the Reference Waveforms in FCPX suggest there is audio given I see peaks and valleys. Channel configuration, when set to mono, even suggest two different wave forms, one for each channel. Also if there is no audio, how is FCPX able to generate a reference waveform in the first place?

Any idea what gives and would it possible to get that audio? Thanks.

Final Cut Pro X, OS X Mountain Lion (10.8.4)

Hi John,

Select your clip in the browser and in the Inspector > Audio tab set Channel configuration to Dual Mono. Then de-select one of the audio channels.



Do you hear audio now?

- Ronny

No I don't. There is no audio playing back from either channel, and yet the reference waveform shows peaks and valleys.

Okay, no sweat. At least this rules out phase cancellation due to improperly wired mics.

You say "some clips have audio, others don't". Do all these clips come from the same camera?

- Ronny

Yes, everything is from a single shoot in a 20-30 minute period. I was told by the shooter he turned off recording audio early on, but not during all these instances. He also mentioned there was a issue with the card switching slots during recording saying slot 1 was full when it was not.

Thank you for the extra information. Do you still have the original camera card or do you have a copy stored on your computer? If so you can check in the FCP X import window if you can hear sound on the original clips. If not I'm afraid these clips may be corrupted, if you do hear sound you could try to re-import the clips and see if that helps.

- Ronny

Alas, I do not have access to the original card with the files/ I suspect they have been written over a few times already. Everything was converted to a .dmg, and its cam footage, so to import it into fcpx requires a pluginin to start. I doubt that plugin could be causing the corruption thought because I get no sound when playing the files in VLC.

I did try reimporting the files from the dmg, but I had the same result. Oh well. Guess its just music overlay time. Still I am left puzzled as to how the waveform references exist without actual sound.

If you cannot hear the audio in VLC either there probably is something wrong with the clips. If the audio metadata is intact on the files but the actual audio track has been damaged this could explain why FCP X can create the waveforms but the sound won't play.

- Ronny

Ronny,

Thank you a billion times over. Someone finally answered how that is possible. Apple discussion had no answer.

I'll add from left field.

On FCXP 10.1.2 and I also had files that had silent audio. That was correct. There was no audio recorded.
... Yet, Reference Audio Waveforms were drawn. The only thing I can think of is there actually was some sort of bleed through or camera noise that FCPX saw as audio and therefore drew Reference Audio Waveforms.

You can see it here. You can see the actual audio is about flat line. It seems FCPX was "hearing" camera noise.

Yup, exact same thing.

Makes FCPX an interesting tool for examining camera noise floor so it seems.