airplay multiple speakers not working in itunes
Hello guys.
When I try to stream music from iTunes Multiple Speakers on my iMac to the Airport Express it only plays 2-3 seconds of any song. The stream then is ended and only the iMac speakers sounds.
The same thing happens when I try to select any Apple TV. It plays 2-3 secs of a song and stops.
If I go to Preferences->Sound and I choose the Airport Express or any Apple TV as the output everything is all right.
Now, you can realize that I have 3 airplay devices and I can't use them all together. :`(
any ideas!??!?!?
iMac (21.5-inch, Late 2013), OS X Yosemite (10.10)