Best hub like apple TV or Airport express etc to use for home with multiple stereo systems

HI, I have 5 stereo systems on my property I get sound to 4 of them through Apple TVs and send via optical from the Apple TV.  This has worked great especially with iTunes, has worked mostly glitch free for many years.  I don't use iTunes as much have resorted to airfoil but it's a little spotty and will drop the connection often and I have to go back to the main computer to reset it.  This is pretty old technology at this point.  Is there something new that works better?  I have mostly trouble with the wireless Apple Tvs.  2 of them are wired via ethernet and those work better for sure.  It's a real pain to try and run ethernet to the other 2 Apple Tvs so I was looking for options.