Exporting to MP4 - Weird Popping Sound

Nierion wrote on 8/27/2020, 5:29 AM

Hey everyone,

Hoping someone might be able to shed some light here for me, I'm pretty new when it comes to video editing. About a month ago I had used the Templates in Video Pro X to do an Intro and Outro for my YouTube. Everything worked perfectly, exported to MP4 and I have been using them on my videos. However, I decided recently to update my Intro/Outro with my own artwork, but I started getting a weird popping sound after exporting to MP4. Tried exporting HEVC also, same result.

Thinking it might have been the audio clip I was using, then I tried just using the same template as before with a different font, I noticed the volume of the sound was a lot lower compared to my original ones (used same template) and the popping was still there, the only thing I had touched or changed was the font (it did the same with the default font too). I've tried exporting with Best Quality, higher bitrates, no luck.

Nothing has changed, my hardware is exactly the same as when I created the original Intro/Outro and the settings are the same too. I have attached a screenshot of what my default settings are and 2 versions of my Outro (Original and the most recent one that has the weird popping sound). Even the overall sound quality is better in the original too.

If you need any additional info from me, please let me know and thanks in advance for any help!

Comments

CubeAce wrote on 8/27/2020, 5:39 AM

@Nierion

Hi, and welcome to the Magix user to user forums.

Audio popping can be an audio buffer problem that can be fixed by going to the program settings and increasing the buffer length slightly. Don't overdo it though. Try in small increments. Do that first and don't be tempted to adjust the amount of buffers to begin with. If that doesn't work, come back.

Ray.

Nierion wrote on 8/27/2020, 6:01 AM

Hey Ray,

Thanks for the quick reply. I tried what you suggested and went to Program Settings. I tried increasing just the Buffer number slightly, and even also tested increasing Multitrack size / preview size (not sure if that would help) as well as switching to Direct sound. I've included a screenshot of what my default settings are. None of the changes made a difference though. Just seems odd that it would get worse when I havent made any changes or even any updates to the software.

johnebaker wrote on 8/27/2020, 6:15 AM

@Nierion

Try playing the audio clip used in the intro in a player, it is this folder -

C:\Users\Public\Documents\MAGIX\Common\Videocontent\Video Pro X\IntroOutro

and is called noisy intro.ogg - you will find it is extremely loud and actually has 'sparking' in it, it is also at the point of clipping the waveform which would add further noise which I think is intentional.

If you want it without the sparking/noise - substitute the noisy outro.ogg file for the intro version - it has no sparking - ungroup all the Intro objects, remove the audio file and drag the noisy outro.ogg to the timeline from Windows File Explorer.

HTH

John EB

Nierion wrote on 8/27/2020, 6:24 AM

@johnebaker

Hey thanks for the info! However if you play both my original clips you will also notice a distinct difference between them and I had made both with exactly the same default settings.

I was also getting the same 'sparking/popping' on a different sound clip I was using when trying to make a video with my own artwork etc.

Nierion wrote on 8/27/2020, 6:26 AM

I would also like to add I get the same popping with the intro template too :)

CubeAce wrote on 8/27/2020, 9:11 AM

@johnebaker @johnebaker

Hi Nierion.

I can only think of a few things that produce audio clicks with digital audio. Clipping, editing a waveform not at its zero crossover point, a buffer under-run or too many buffers set for the amount of memory.

As your sound settings appear to be the default and the same as mine, for the time being I would rule that out.

If the file has not been edited we can rule that one out.

If you are running other things in the background that could cause a memory related problem.

If there is nothing additional running we could possibly rule that out as well.

I'm not overly sure how MEP treats data within the editor so there could be some variation involved there.

I'm tempted to ask if an exported file displays the same defect or if you can play the file in another program does it still give clicks?

What I do notice in your export dialogue is the very low average and maximum bit rates set for the project resolution and relatively low bit rate of the audio. Also your GOP length is not either the same as your frame rate or divisible by it.

Any of which could potentially cause problems.

If it turns out it's none of those try exporting the file and playing on an outside source. If there is nothing wrong with the playback, then heaven forbid it could be your motherboard sound module capacitors wearing out or outside electrical interference, although the last one is less likely.

Difficult to pin down when we can't replicate the problem. It could be any of the above or none of them. Something I haven't thought of.

Ray.

Nierion wrote on 8/27/2020, 10:00 AM

Wow, certainly a lot to take into consideration. So, I've had my computer off for the last few hours, turned it back on. Decided to test both my own custom Intro with my own artwork and audio clip and the template provided, did an export twice on each one just to be sure, ran the audio bitrate at 192 and it's fixed.

Weird though, as I had tried running at 192 earlier. I'll consider this a success and take in the fact I learnt quite a lot from your advice as well, so it's greatly appreciated. Like you said maybe it was a memory related issue.

I'm still a novice at video editing, but it's definitely been a fun learning experience. Thanks again :)

CubeAce wrote on 8/27/2020, 10:46 AM

@Nierion

After what you have described I would suspect the overall bit rate for your project is too low. If you don't allow enough headroom in the bitrate count it can have adverse effects on either picture quality or audio quality. Something would have to give and it's sometimes random which becomes worse. The audio or visuals.

I have put my project settings up for a similar export of the same resolution. I did it in MEP rather than VPX but the settings would be the same setup whichever program I used.

Compare them to your settings you show in your post. There is a big difference. Yes you could cut down a bit from my settings but not as low as you have them set. I personally would not be happy with that as an export setting for that project. Also the GOP number should be preferably be either 30 or 60 in yours.

Ray.

Nierion wrote on 8/27/2020, 10:59 AM

Makes sense. I'll definitely take that into consideration when exporting. I think the reason I had started using lower bit rates was due to filesize, but since then I have started using Handbrake to compress the file sizes if they are too large for uploading.

Thanks for your advice. :)