[Jonathan Fairey]

Hi Craig,

Thanks for your advice – you hit the nail on the head. Soundtrack Pro flagged up problems with the phase of the audio. Fixing it in Soundtrack Pro has resolved the problem.

I am still not entirely sure how this occurred – the sound for that first interview clip was recorded using the same equipment, techniques and team as all of the other footage, and I’m still unclear as to why the phase issue seems to only affect certain machines – possibly the PC laptops I was testing it on just have one speaker, so the Macs are playing it back in stereo whereas other devices including phones are sending the stereo audio out through one speaker, which is where the problem arises?

Either way, I have fixed the problem now. Thanks Craig for your understanding and feedback (even though this turned out to not be a compression issue at all!). Hopefully this thread helps anyone else who has the same problem in the future.

Jon

[Jonathan Fairey]

Hi Craig,

Thanks for your feedback. I will investigate and let you know how I get on.

Thanks again.

Jon

[Jonathan Fairey]

Hi Craig,

Thanks for your quick response, and apologies for not noticing the sticky thread – it wasn’t my intention to waste anyone’s time.

The video plays back with no issues on all Mac machines I have tested it on – these have 10.6.8 and 10.7.4 (Snow Leopard and Lion). I have also tried it on two Windows laptops, both running Windows 7 version 6.1, this is where it fails to play back the audio for the first interview shot. It also fails to play the audio for the shot on an iPhone 4S running iOS 5 and on a Samsung Galaxy S2 running Android 4.0.4.

I have been using Final Cut Pro 7.0.3 and tried exporting in the following formats:

MP4 – H.264 codec, audio format AAC-LC (data rate 256 kbps, stereo 44.1kHz)
MOV – H.264, ProRes, each with 44.1kHz audio, Format: Integer (Little Endian), 16 bit sample size stereo.
AVI – Cinepak compression, audio uncompressed at 44.1kHz (picture looks shitty but at this point I was just seeing if anything would fix the audio – it didn’t work).

Looking at the video in Windows Media Player, Quicktime, and on Youtube using Firefox and Chrome all produce the “missing audio” effect.

The file is to be played on a PC laptop, and possibly projected. It will also ultimately be put up on YouTube, but at the moment I am only using YouTube to show drafts to my client – the main focus is on getting a playable copy on a PC laptop.

Again, to reiterate – the audio is not present when played on PC machines and phone handsets, either from the hard drive of the machine or when viewed on YouTube. Plugging in a pair of headphones seems to magically fix the issue. I have tried compressing the audio separately, as a .aiff or .wav and then putting that into Final Cut so there is only one audio track but that hasn’t had any effect. The video plays back without any problems in Final Cut also, and there are no filters on that audio region that aren’t also implemented elsewhere in the video with no adverse effects – just light compression and a small amount of gain.

If anyone has any suggestions, I would be very grateful, and thanks again Craig for taking the time to respond.

Thanks,

Jon