I use MapFactor on my phone Samsung S3 joined to my car stereo with Blue Tooth.
I have check "sound volume custom" in expert options because, when I use MapFactor I also listen my playlist in the same time and I have to adjust the volume of each app (MapFactor and Musicplay).
But why I hear the MapFactor announcements in first on my phone and in second time on my stereo car?
That is a very unpleasant echo with MapFactor but not with the song on my app MusicPlay.
And if I lower the global sound level of my phone I don't hear my playlist musics.
Thanks for your answer but it's not the solution for my problem.
I tested with this app but the echo is always here.
I'm very surprise that nobody have this problem: the MapFactor announcements are in first go out of my Samsung S3 speaker then, after 1 at 2 seconds, goes out of my stereo car speakers connected with Blue Tooth and create an echo.
But, if I think that Blue Tooth made this delay (and produce this echo), why the other Androïd apps (example: Music Player) automatically stop the sound of my Samsung S3 speaker (and delete this echo) when I connect my stereo car with Blue Tooth?