Obs is heard 2 times

[Gabrielaz07]

When I play a multimedia source, the sound ssle 2 times, once through the source and once through the desktop. Before this did not happen to him. and the only solution now is to mute the output and only hear it live. and it's a bit annoying because I can't control the volume, I've installed oba on other PCs to see if this happens and no, it doesn't.

 

[konsolenritter]

Both should be live. WIth "output" you mean the audio track of the actual playing source, i think.
This track as well as the global "desktop audio" should appear both within the obs audio mixer. Do you see them both there?

Right, just mute one of them. Mute those one which is more "off-sync" (playing a slightly bit later).
If these hints doesn't work for you, you have to provide an obs-log here for us to see your actual config of scenes and sources.