No audio on macOS QuickTime MPEG-4 Video

I'm wondering what can prevent the Quicktime player from playing the audio track alongside a video.

The files I have are MPEG-4. When it is launched on macOS QuickTime, there is no sound. I've tested it quickly on an iPhone, and audio is played when the same files are launched. Elmedia Player also successfully produces sound on the same computer.

How can I fix the problem that prevents QuickTime from playing the audio track?

How can I remove the audio track from a video that I have already uploaded to YouTube without having to create / download a new video?

Battery Exchange Network

The Stack Exchange network includes 175 question-and-answer communities, including Stack Overflow, the largest and most reliable online community on which developers can learn, share knowledge and build their careers.

Visit Stack Exchange

I produce and compose your song for $ 110

I will produce and compose your song


I am a professional producer and guitarist / songwriter. I compose and produce your song and give it all the attention it deserves. I'm proud to play and produce to be creative and find new ideas to get the most out of your music.

Prices may vary depending on what is involved, so send me a message so we'll all talk about it first.

Thank you, I hope to hear from you soon.


I will publish an article on the website of 51 DR Audio for $ 70

I will post your guest commentary on a well-known audio website, 51 DR, which promotes independent artists, reviews the latest audio technologies and

by: outreachpros
Established: —
Category: Guest Messages
Views: 125


ffmpeg – How to remix / combine two lossless MP4 files: one has the video I want and the other has the corresponding audio I want

I would like to know if there is a way to transfer / combine two MP4 video files.

They both have exactly the same number of images. One is in 1080p without sound, the other in 720p with sound. I would like to permanently combine the two. The result will be a 1080p MP4 video with sound. And I would like to do it without loss, both for video and audio, a kind of 1: 1 transfer.

Preferably using FFmpeg. Any help is extremely appreciated.

audio – Is there a way to force AAC on a Bluetooth headset?

Macos connects to my headset for the first time and uses AAC.
On other connections, it will switch to SBC and the quality is beyond terrible.
The only solution I've found is to "forget" the headphones in question, then reconnect them, because a brand new connection coupling brings quality back to the AAC.
I've checked a second time with Bluetooth Explorer that my options are correct and also checked with other headphones. This happens on both pairs.
I guess this has to do with the headset's microphone, but I have not had any permanent chance to try the vague advice from Apple to stop offending apps and change sources, and so on. , advice that I found here.

Does anyone know a permanent fix to stop the continuous downshifting of the audio codec?

I'm not sure which version of OS X it started on, but it's been at least a few months now. I am currently running 10.15.1 on a 2017 touch bar macbook pro.

podcasting – How to allow a user with a contributor role to upload audio in a message or message?

I have problems so that the user can download an audio file or podcast into an entry. I have to do it without the help of a plugin because we will not follow the website.
My question is: how can I make it so that the user with a contributor role can load an audio file or podcast into an entry without using a plug-in?

unit – Why, when you change the cursor of the UI, the slide in the audio mixer drops the volume at the end?

The script :

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Audio;
using UnityEngine.UI;

public class SettingsMenu : MonoBehaviour
    public AudioMixer audioMixer;
    public Dropdown resolutionDropDown;

    private Slider _volumeSlider;
    private Dropdown _dropDownQuality;

    private Resolution() resolutions;

    private void Start()
        resolutions = Screen.resolutions;

        List options = new List();

        int currentResolutionIndex = 0;
        for (int i = 0; i < resolutions.Length; i++)
            string option = resolutions(i).width + " x " + resolutions(i).height;

            if (resolutions(i).width == Screen.currentResolution.width &&
                resolutions(i).height == Screen.currentResolution.height)
                currentResolutionIndex = i;

        resolutionDropDown.value = currentResolutionIndex;

    public void SetVolume()
        float volume = _volumeSlider.value;
        Debug.Log("Volume " + volume);
        audioMixer.SetFloat("MusicVol", Mathf.Log10(volume) * 20);

    public void SetQuality()
        int qualityIndex = _dropDownQuality.value;

    public void SetFullScreen()
        Screen.fullScreen = !Screen.fullScreen;

I've tried to solve the problem using math.log and doubled by 20:

audioMixer.SetFloat("MusicVol", Mathf.Log10(volume) * 20);

In the cursor editor ui, I have also changed the minimum value to 0.0001, the maximum value to 1, and the current value to 1.

Volume ui slider and Volume slider of the music group's audio mixer

In the screen capture, you can see the yellow VOLUME slider on the window at the bottom left. The cursor is near the end on the left. I moved it to the left.

But right in the music group, the volume is only 20 and if I move the yellow slider ui to the left, the volume slider in the audio mixer in the music will go from 20 to -80 instead It should slide slowly slowly depending on the speed at which I move the yellow slider in the UI.

Google Hangouts: How to allow dialing for the audio side?

I see how to call OUT from a Google Hangout conference.

My question is different: when I create the Google Calendar event and set up Hangouts as a conference / video service, I need invitations to do all this (invite people to the video part as it is done) and ALSO include a numbering. number for people who are only on phones, including desk phones (for example, not just mobile phones).

The ko I found on this topic is about organizations that use meeting places. I just use a Google personal account.

How to solve?

(I have my own Google Voice number / account, if it helps.)

imac – Why can not I direct the audio of a video on my internal speakers?

I have an iMac connected to a movie screen. I recorded a video on the secondary monitor (the Cinema Display) with OBS. To get the sound in OBS, I used the plugin. iShowU AudioCapture and I set up a multichannel audio device in the Audio MIDI Configuration MacOS settings to be able to listen to audio while recording it at the same time.

(The source is a third-party application that provides a video and audio stream.)

Now, something funny happens when I want to play the video with VLC: I can only hear the sound when I use the secondary monitor as an audio device in VLC.

I can hear a youtube video being played on my iMac (main monitor). But I can not hear the audio channel of the recording, regardless of the output that I have chosen. It feels like VLC remember where he recorded the sound and only plays it on the original source. Which is (in my opinion) totally crazy.

Can any one explain this behavior?

My audio output options are:

  • internal speakers (it's the iMac, I can listen to youtube here, but not the VLC video)
  • audio display (this is the secondary monitor, the Cinema display)
  • G533 game headset (it works too, I can hear the video on the headphones)
  • device with multiple outputs (this is set up for recording so that it can listen to the audio AND route it to OBS)
  • iShowU Audio Capture (a plugin needed for OBS to listen to internal audio)