Strange Audio issue on Mobile Devices - Video taken with Sony HD Cam

[timothy001]

Hello

I am running in to a strange audio problem on some of my videos. I recorded a music band with an external mic plugged in to a decent Sony HD video camera. I recorded about 90 minutes of HD video. The camera created four 2GB .mts files, which I copied off of the camera and onto my computer. I believe the format is AVCHD natively.

Anyway no matter what I convert to, mp4, divx, avi, and upload to youtube (or even upload the MTS files directly) I have a strange audio issue. On a computer desktop, I can hear the music no problem at all and the video quality is great and plays with no issue. On an ipad, it is fine also.
However, on an Android device, either from the mobile youtube site, or the youtube application, the audio is like at a volume 1, and extremely distorted. These are the same videos that work on a computer or ipad The video quality is fine. If I plug headphones into, or stream Bluetooth from the Android device (either a galaxy s4, or a note 2), the audio sounds just like it should from tehse videos that have broken audio through android external speakers. What could be wrong with this?

Thanks in advance for any help.

[Baldrick]

Do you have an audio sample? Or youtube example?

[timothy001]

https://youtu.be/X8v30_r-nio

Here is one

This sounds squished and low volume when played on a galaxy s4 or galaxy note 2. However it works fine from those two devices when playing through headphones or streaming bluetooth.

Thus youtube vid also works ok from a pc or ipad. It was an mts file saved to an mp4 then uploaded. Really strange issue.

[Cornucopia]

Sounds like an out-of phase issue, possibly compounded by recompression complications. And was this recorded in surround by any chance? Could be that downmixing has been done incorrectly.

Model #s for all devices (including the mic) and MediaInfo detailed reports of before & after clips can help somewhat, though phase issues cannot be clearly ruled in/out by metadata alone, so sample clips may be needed.

Scott

[timothy001]

I can get the model numbers. Even uploading the .mts files directly to youtube from the SD card of the camera the audio has the same issue. Same as if I convert mts to mov, avi or mp4 so far.

[timothy001]

Sony HXR MC2000 and audiotechnica mb 2k

[timothy001]

I was reading a few other posts. I am wondering if there is an issue with the left right audio tracks, and the videos work in stereo output mode, like on a PC, or through headphones or bluetooth, but not mono mode like through an android external speaker. How can I check this, is there any software which would let me see the audio tracks, left and right?

[theewizard]

did you redo the audio to a lower bitrate AND STEREO in any of the uploaded videos ?

what is the sampling rate

seems to me you have exceeded the range that the android single amplifier circuit can handle

i think you need to resample the audio and reduce the specs, for processed uploads , BEFORE upoading, IF your worried and want android users to watch from youtube

[timothy001]

I just tried 96kbs the lowest avail bit rate and mp4 conversion from the .mts file and it still sounds squished and low. . I'm trying to see if I can view the left and right tracks but can't find free software that will do it.

[theewizard]

bitrate and sampling are two different settings

also what format is the audio track ? mp3, acc ?

oh have you tried this with somebody's elses phone ?

maybe the android phone has an audio problem

[timothy001]

Yeah it doesn't work on a note 2 or a galaxy s4. What is considered a low sampling? I havent tried that yet.

[timothy001]

Thank you! It's fixed. It was an out of phase issue like you suggested. I copied the left track over to the right track, and it's working now. Some kind of stereo, mono issue with Androids. I used Adobe Creative Loud to make the changes and export in MP4 format.

[Cornucopia]

If you copied the left over to the right, all you have now is a mono track. It does fix the problem (and it verifies what I was thinking about the phase, because a duplicated track would have identical phase), but you no longer have the spaciousness that your original had.

To correctly fix, you should:
1. Load your clip audio into your editor of choice
2. Select EITHER the left or the right (doesn't matter, but you should only select ONE of them)
3. Invert the phase of the selected track (IOW, signal levels above the midline move to below and signal levels below the midline move to above).
4. Re-save/Re-export.

DONE. And it's still in stereo, with spaciousness.



Scott