Prevent mplayer from changing system volume

Question

When I change the volume in mplayer it also changes for other applications. How can I configure mplayer to only change its own volume? Or is this a problem with the rest of the audio stack? I am using alsa with esd.

Answer 1

mplayer takes a -softvol flag that makes it use the software audio mixer instead of the sound card. If you want it on permanently, you can add the following to ~/.mplayer/config:

softvol=true

Answer 2

short answer:

put this in your config

ao=pulse

explanation

By default mplayer uses Alsa as the audio output interface and your sound mixer is probably pulse audio. This works, because pulse audio has an alsa interface for backwards compatibility. When you tell mplayer to use the actual pulse audio interface, it can send signals to pulse to only change the volume of that instance of mplayer and nothing else. Then changing the volume will not change the global volume anymore, but the application volume slider. When you open pavucontrol and change the volume in mplayer, you will be able to see how the volume of the application will change.

When you actually have only Alsa on your system, then you should probably change that. When that is not an option, then softvol=true is probably your solution.