Hi there Stu,
It sounds like you want more control over what songs sync to your iPod from your computer. There are a few ways you can go about that, but the most common is to select genres or albums or artists you want in the Music sync settings in iTunes by choosing "Selected playlists, albums, artists, and genres" rather than "Entire music library"
iTunes 12 for Mac: Sync iPod, iPhone, or iPad
You can also manually add content to your iPod with these steps from the following article:
Check to make sure that the "Manually manage music and videos" option is turned on:
- Connect your device to your computer.
- Open iTunes. Make sure that you have the latest version.
- Locate and click on your device.

- In the left sidebar, click Summary.
- Scroll down to the Options section.
- Click the box next to "Manually manage music and videos."

- Click Apply.
You might see a message that your device is synced with another library. This means that you've used a different computer to sync your device in the past, and iTunes can't sync without first erasing and replacing all iTunes content on your device.
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