Why can people listen to what I'm hearing through my headphones?

[Ammar666]

I use my iPhone earphones to have Skype conversations with my friends/family. However for the life of me I cannot figure out why they can hear whatever it is that I listen to when I'm having the Skype conversation. For example if I play a video during the Skype call, they will be able to hear the video even though I'm playing it through my earphones only!

How is this possible and how can I fix it?

 

[617aircav]

Mute the video.

 

[vkd]

It is because all the sound out of your device goes through the same channel, that means sound out of Skype and sound out of a video go to the same sound channel, which you have plugged headphones into to receive. Regardless of how you are receiving the sound, on a hardware level it is quite simplistic and only one channel is in operation.

 

[Ammar666]

It is because all the sound out of your device goes through the same channel, that means sound out of Skype and sound out of a video go to the same sound channel, which you have plugged headphones into to receive. Regardless of how you are receiving the sound, on a hardware level it is quite simplistic and only one channel is in operation.

The thing is that it doesn't always happen. It does happen on most occasions but not always. I'm using a 12-inch MacBook and this never happened on my old 2013 rMBP.