Airplay won't connect to remote speakers
I have a mbp 10.11.3 and iTunes won't connect to my remote speakers through airplay. Nor will my Airfoil connect either. My other, older mbp will connect with airfoil, but iTunes won't connect on that machine. The machines connect on a network with two base stations. The Airport Express is around 12 years old and isn't supported in Airport Utility, so I don't think I can do much with that other than reset it, but if I do that, it may never connect to the network again. It is plugged into speakers with a 1/8th inch jack, and it gets its feed from ethernet that comes from a time capsule.
Anyway, any ideas about how to reconnect to the speakers from Airfoil and iTunes?
MacBook Pro (Retina, 13-inch, Mid 2014), OS X El Capitan (10.11)