Hello community.

It is the first time ever, that I actually ask something in a forum myself. Most time someone else had the same problem already and I found the solution somewhere in the Internet, after a bit of researching.
BUT, there is always a first time and here I am, a self-taught video/audio editor, still at the beginning of learning.
Let me explain my problem: I create semi-amateur Youtube videos about my Canada traverse by bike. Those videos consist of cellphone video clips, image sequences and background music, which is actually in the foreground while the slide shows and quiet while the clips are playing. The music source is mp3, but good quality, minimum 192 kbps, which gets converted into wav in kden anyway.

Because I found out about LUFS in regards to Youtube, I started to export the complete audio of my project as a wav, imported it in audacity, checked and adjusted the LUFS and saved it as a processed wav.

I also rendered the actual video as a mp4, mute. A classic situation. I start a new project where I put both in it. All looks and sounds perfect. I also tried commands for ffmpeg in the terminal, where I merge both, video and audio but it did not work. The video stayed silent in the output file. It only worked, when the video still had the old audio and I swapped the audio files. Some syntax problems I guess. I am really not that deep into the ffmpeg command rabbit hole.

HOWEVER, here is the PROBLEM! The perfect sounding wav audio gets compressed during the rendering process and in the finished mp4 it sounds at some parts very tinny, like if the audio would be 64 kbps or so. Very hard to describe. And it is only at some parts, maybe when the audio reaches certain frequencies? It drives me nuts, because I can't get it right and I don't know what the problem is. Or let's say, I assume it has something to do with the audio codec but why is it doing that?

Here is a short section, video and audio together for you to check what I mean:

https://www.dropbox.com/s/azlmpatc7x2lr ... d.mp4?dl=0

That is the short part in the video where it is very obvious. Especially when the singer sings the words "ever and ever" at 5 sec and 11 to 13 sec. But actually you can hear that tinny sound almost the whole clip. It must be a codec/quality issue.

I tried something else before that post. I merged video and audio and had it export as .mov or .mkv. Therefore the audio does not get compressed. And surprise, the file of course is bigger but the sound is as it should be. I can call it a day now and do that from now on all the time. BUT I want to learn and fix that issue. Any ideas, community?

Greetings, Erlendur

The default audio codec for MP4 (on kdenlive) is the AAC... have you tried to increase the quality to 256 (default is 192) ?

P.S. i downloaded your video and the audio is; AAC LC 192kb/s 48Khz stereo. (you have to increase this)

Also you can find a 320Kb (and a 384k) profile on rendering-profiles downloading section...

Hello, bartoloni,

it has been a while since I posted that issue. It still remains but I found a workaround. Now I render video and audio separately. Then I check the LUFS of the complete audio, adjust it in Audacity and then I use ffmpeg commands to merge the audio and the video file. I do not re-render it with ffmpeg, because I had similar, tinny sound results. Instead I just merge them together, which means a bigger file but at least the audio stays untouched.
Not optimal, but I tried to increase the kb/s, of course, but it did not change anything. I will have a look into this rendering-profile section. I am kinda pausing producing videos atm, will do one last one and do the rest of my journey at a later day. I will keep in mind what you told me and hope I can fix that problem. Thank you.

bartoloni wrote:The default audio codec for MP4 (on kdenlive) is the AAC... have you tried to increase the quality to 256 (default is 192) ?

P.S. i downloaded your video and the audio is; AAC LC 192kb/s 48Khz stereo. (you have to increase this)

Also you can find a 320Kb (and a 384k) profile on rendering-profiles downloading section...