Airplay compatibility with G4 Macs

My WiFi soundsystem has an Airport Extreme base station and an Airport Express node connected to a Bose sound system. I have a Macbook Pro (2014) and an iMac G4 (the "jetsons" with Mac OS 10.4.11) that is hardwired (LAN ethernet) to the base station. Sound system has worked for @ 10 years until I replaced the worn-out Express with a new one last year. The G4 now appears not to have Airplay capability anymore (I can't find it on Airport Utility) and the G4's ITunes (version 9) will not show multiple speaker options.

Can I restore this G4 back to the Airplay WiFi network?

AirPort Express

AirPort Express

Product No Longer Available

No Answers have been submitted