I have iTUnes v. 12.4.3.1 on my MacBook Pro v 10.8.5. i have 558 songs in a number of playlists. I backed up my music before I upgraded my iPhone 6 to an iPhone 12. when the download was finished, I lost songs, they are still on my mac, whats up???

Media is not included in device backups. It would need to be synced from your library. I'm pretty sure that you cannot sync your iPhone 12 with iTunes 12.4.3.1. A workaround might be to subscribe to Apple Music so that your music can sync over the air.

Minimum requirements for syncing to iOS 14 are iTunes 12.8.2.3 or better running on OS X 10.11.6 El Capitan or better.

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If you still have content on a device see Recover your iTunes library from your iPod or iOS device - Apple Community. Apple make casual copying of media from devices hard, but it is possible. You're supposed to keep all of your media in an iTunes library which you also backup. You're not supposed to keep digital copies of music if you sell the original CDs.

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What are you using to play the tracks at the destination? The same MacBook you use at home or something else? If something else Is your library supposed to be synced automatically via iCloud Music Library, i.e. do you have a subscription for either Apple Music or iTunes Match. iTunes really shouldn't be used in a performance environment. Something professional like QLab is a better bet.

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I have a similar problem: cannot upload music to my iPhone 11 from my MacBook Air. Even if I try to restore from iClaud a lot of the albums are lost. Unfortunately Apple discontinued iTunes the easy way to transfer music. It seems they want to sell you more music from Apple Library, which will drive some people away from Apple products. I guess they think they can afford it. That used to be called loyalty to your customers.

So not only does apple not allow your private music transfer they also disallow album art work. So now that i have lost all my personal music ( I sold off all those cds thinking that they were safe). Yes that also means that iCloud back up will not work for transferring your property. Thanks apple

I create playlists for performances on my Macbook at home and the songs all play fine at home ... When I arrive at my performance destination and use my playlists, several songs are NOT highlighted and are SKIPPED, so I cannot play them! I sing for a living, perform daily, and NEED this issue corrected IMMEDIATELY. ANY advice you may offer is greatly appreciated. Thank You

You're welcome. 🙂

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You should still be able to sync music from your library to your device. What version of OS X/macOS do you have installed? What version of iOS is on your device?

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