All is in the question…but
I mean different mediaplayers in different songs.
Right now I need to mute one by one, in each states of each songs. Quite long operation…
I thank you all for giving me your point of view, ideas.
David
Unfortunately not. 
Ok. You save my time for searching.
.
As you can see I am using more and more deeply your programm. I think I am a big fan of it!
The global idea to have one binding to control several other bindings is a bit strange…
Or something like linking bindings…
Have a good day!
David