Cisco 1941 Cisco 1142 AP - iTunes airplay wont stream music

Wireless laptops with iTunes cant play music to Apple Airport Express. My home network is made up of; Cisco 1941 router with 8 port EHWIC with POE Cisco 1142 AP for wireless Apple Airport Express connected to LAN (wifi turned off) for iTunes Airplay. All wireless is VLAN 50 All LAN is VLAN 10 Apple Airport Express is VLAN 50 All works fine except iTunes on mac laptops or windows laptops can not play wireless music to Apple Airport Extreme (wireless N, VLAN 50) Interestingly, iPhone (wireless G, VLAN 50) can play wirelessly to the Apple Airport Express. From google searching and trial and error I suspect Multicast Groups and Bridge Groups need to be setup correctly on the Cisco 1142 AP and Cisco 1941 Router. This is a little bit beyond me.