Music not syncing from Mac to iPod

Hi, I am using an iPod touch and am an Apple Music subscriber.

Until recently my iPod had all my music downloaded. Most of it was from my Mac where I had ripped CDs over the years. Then the other day loads of my music disappeared. I couldn't get the iPod to sync, wired or wirelessly, with the Mac. I wiped the iPod and re-downloaded everything. However, the tracks that are not found on Apple Music (which oddly incudes random songs on various albums, but significantly it includes the tracks that Apple Music does not have, such as things I've taken from vinyl) are not syncing. When I try to sync now it acts like it is doing it - runs through stages 1-4 almost immediately - but doesn't actually copy anything.

Any thoughts?

Chris

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