Accessing iTunes library to play through Yamaha music cast app

I can’t get my IPad (new one) to play iTunes through MusicCast, But I can with my IPhone. Here’s my setup:

I have thousands of songs stored on home computer ITunes. 80% of these are from my personal CD collection, 20% are purchased through the Apple Store. I pay monthly for Apple Music and for ICloud.

I have 4 Yamaha WXA 50 amps connected to my internet. My home computer and all apple devices are connected to the same internet. I have the music cast app on both my IPhone and IPad. Both can source music from a variety of sources like net radio, Sirius, pandora, etc. But only the IPhone will source my ITunes Library

I have variously synched my devices.

My IPhone picks up my library and playlists via ICloud. I can access songs and playlists to play either directly through its speakers using the IPhones Music app (ITunes), or by asking music cast to access by selecting My IPhone from the MusicCast source screen (menu). My libraries come up as do my playlists, and I can click and play through MusicCast to my amps.

My IPad picks up my library and playlists too, but I’m only able to play through Apple Music App. To the IPad speakers. When I go to Music cast it shows my IPad as a source, and when I click on that I get my library and playlists showing, but all grayed out and unable to click and play.

So, why are these two devices working differently, and/or what am I overlooking to get my IPad to have non-grayed-out lists? I don’t believe this is controllable from the home computer end, or is it?

Don’t know if this is relevant but settings/general/about shows 280 songs as being stored(?) on my IPad, and 2250 stored on my IPhone. Both devices show exactly the same number of videos and photos. As I said I have over 7000 songs in my library on my home computer so I have no idea what or how 280 or 2250 songs have decided to store on my two devices…

Any help GREATLY appreciated. Thanks.. Eric