ITunes won't connect to my Airport Express

Question

I have four airport express used for airplay.  Recently they all stopped working from the PC.  I can stream music to them from iPad and iPhone.  They show up under multiple speakers but are not options to select.  Very frustrated!  Please help if you can!

Answer 1

The following commands seem to put things back in order after Airplay device can't be selected.  It seems somehow Cisco Anyconnect may re-enable IPV6 after it's run.
From terminal:
# networksetup -setv6off Ethernet
# networksetup -setv6off Wi-Fi
Then I created a script to constantly ensure that ipv6 is disabled, that way, when ending my Cisco VPN session, things go back in order within X seconds
termusername = string result when you open terminal and type "whoami"
keepv6off.sh:
#!/bin/bash
while true; do
  /Users/termusername/scripts/newnetworksetup -setv6off Wi-Fi
  sleep 45
done
newnetworksetup:
networksetup ${1}
chmod 755 keepv6off.sh
chmod 755 newnetworksetup.sh
Now exit /etc/sudoers from terminal to allow networksetup to be run without prompting for password every time.
# sudo visudo
termusername     ALL=NOPASSWD:   /Users/termusername/scripts/newnetworksetup
Now use "launchd" to automatically kick off this script when you log in:
cd /Users/termusername/Library/LaunchAgents
create com.termusername.keepv6offscript.plist text file in above directory as follows:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
   <key>Label</key>
   <string>com.termusername.keepv6offscript</string>
   <key>Program</key>
   <string>/Users/termusername/scripts/keepv6off.sh</string>
   <key>RunAtLoad</key>
   <true/>
</dict>
</plist>
save it
now run
launchctl start com.termusername.keepv6offscript.plist
you should be able to run 'ps -ef |grep keepv6off' and see an entry for this process running at this point.  This script will ensure ipv6 is off every 45 seconds.