Itunes Metadata not syncing when transferred to SSD.

Hi all,

Some time ago I decided to completely rework my Itunes library. This includes converting my .WAV files to .AIF files with a nifty converter-app, completely re-writing the metadata and adding album covers in Itunes.

Because I'm running out of storage capacity on my macbook, I also decided to transfer my complete music collection to an external SSD. This last part is giving me a lot of issues and headaches.

Occasionally when dragging a reworked song from Itunes to the SSD folder, it would transfer everything just fine, but most of the time the preview icon disappears and when I click on Get Info, I see that all the Metadata I just wrote is not showing anymore.

Is this a more common problem and does someone know how to fix this issue?

Kind regards