As we speculated in our previous post, Apple has restored the much commiserated removal of Home Sharing from the Music app in the recent release of iOS 9.
You switch it on the same way you did prior to iOS 8.4 which bizarrely removed the feature without any notice. We guess that it was removed because of Apple's desire to ship 8.4 with Apple Music which entirely replaced the previous music app, and now they've had some time to re-add the missing component.
For anyone who doesn't know, Home Sharing for the Music app gives your iPhone / iPad the ability to stream music from an iTunes library running on a desktop version of iTunes. This is of course of interest to iHomeServer users many of whom use iTunes on a headless server to consolidate their personal music library and then stream from that library to all their devices. This was no longer in the iOS 8.4 update but fortunately, is now fully restored in iOS 9.
For more details on how to enable it please see this link: https://support.apple.com/en-gb/HT202190