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macrumors member
Original poster
Feb 8, 2007
On my 2015 retina MBP, running Handbrake 1.0.1, on Sierra, I get no audio on the .M4V files I am trying to create from old .mov files.

With the exact same file, on my 2012 MBP, running Handbrake 0.10.0, on El Capitan 10.11.6, I get audio perfectly as it should be on the .M4V files I am creating from the same exact .mov files.

I would prefer to use my 2015 machine as it's a quad core processor and will be able to handle the 850+ videos that need to be converted in a batch much faster than my other machine.... but I'm running out of options and need to get them converted.

Any ideas why the difference? Thanks!


macrumors member
Original poster
Feb 8, 2007
Also, this is what the log is showing repeatedly:

decavcodec: hb_audio_resample_update() failed


macrumors 68020
Apr 23, 2010
To play a little bit off your log, it would seem you're missing an audio codec on the later machine. For most people, how codecs get installed on their system is a bit of a mystery, usually getting installed with apps over time. So if you have Compressor, QuickTime Pro, Adobe Media, etc on the older laptop, but not on the new, that could account for the difference. I am unaware of a simple way to scan for codecs on mac os x - through someone else may know of a way.
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Aug 26, 2014
Can you get the tools via Xcode's extra tools? I already have Compressor and all that other stuff including the Xcode audio tools, so I can't "break it" to see if installing Xcode, etc would help. I hope this helps a bit. Let us know how it goes. I'm a big fan of Handbrake. And Compressor. Multiple Macs on ethernet? Buy Compressor. It's totally worth it for the distributed processing alone. -That's my opinion. YMMV.


Jun 30, 2007
You can use a program such as MediaInfo

to determine what codec was used to code the movie.

(When in the finder if I am previewing a movie with the space key, I've found that I have to change the extension from .m4v to mp4 or it will not display.)

You can check /Library/Quicktime/ to check which Quicktime components are installed. In my case I have:

FCP Uncompressed 422.component
DVCPROHDCodec .component

Here's the handbrake documentation on audio codecs:

Unfortunately I couldn't find out which ones Handbrake can read, but that's not your issue so it's not relevant.

Since the same file plays fine on another system then it definitely implies you are missing a codec for playback.

What software are you using to play the movie? Does it allow you to see the audio tracks? If there are multiple tracks, does another track work?

Did you ever install Quicktime 7 on the system where it works? It allow you to play older media formats:


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