Audio recording intermittently Canon 5d mark iii

Issue #2366 new
Mark Davis created an issue

Was wondering if anyone else ever experienced this issue. I've not been able to find a resolution on any of the forums, google, etc.

I've noticed that when I am shooting 1920p ALL-I with the raw_rec module loaded but not engaged, in other words with RAW video turned off, my regular h.264 video files will often be without an audio track.

Even if I am shooting clips without changing any settings or turning the camera off or on, some will be without audio and some will have it.

I know that you have to load mlv_raw and mlv_snd to get sound with the RAW recordings, but is it necessary to have those loaded when using magic lantern in order to get sound on canon's native h.264 files? I wouldn't think so because some h.264 clips have sound but...

Also, I have magic lantern loaded on an older 2GB SD card and was wondering if the speed of that card would have any effect on the magic lantern software.

I am using magic lantern build: magiclantern-Nightly.2015Apr28.5D3123

I am using SanDisk extreme pro 160MB/s card 64GB.

Does anyone have any recommendations for this issue or maybe someone has experienced this?

Also, FPS override is off. I've heard people having issues with audio with it on.

It's extremely unsettling as any reference audio for interviews, etc...will be missing and if I'm not using a clapper nothing will be able to be sync'd.

Any and all help would be greatly appreciated.

Also, this is my first post so please let me know if this is the right place for this.

Thanks very much,


Comments (4)

  1. Licaon Kter

    Any reason to activate and/or use raw_rec instead of the newer mlv_raw ?

    Since raw_rec is no longer developed ( afaik ) the advice would be "disable raw_rec".

  2. Mark Davis reporter

    Thanks for your quick response.

    Well, I guess the initial reason was that I was getting the pink corrupted frames occasionally with the mlv_raw and the mlv_snd modules on. But I guess I could try using just the mlv_raw and not use the sound module. Do you think that the corrupted frames are due to the additional processing requirements of the sound?

    Anyway, wasn't getting the corrupted frames using the raw_rec.

    As a side note I am able to reproduce the lack of sound error on the h.264 recordings:

    If I record raw with the raw_rec and then go back to magic lantern menu and turn off raw_rec, the next group of h.264 videos will have no sound. But if I record raw and then press the playback button as if I was going to review a clip and then press it again to come back to live recording, my sound is back on again.

    Could be a workaround for now. But I will try the mlv_raw. I didn't know it was newer, so maybe I will give it another shot.

    Also, do you know if most people recommend disabling most of the other modules like the focus peaking, etc...when using raw so that the camera and media is less overwhelmed from a processor standpoint? Another thing I could try I guess.

    And finally, do you know why people get the pink frames? (Where the image is there, it just looks all weirdly colored) Is it a speed thing? Or what?

    Thanks very much for you input on this. I really appreciate it.


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