1st Generation iPod Shuffle? There are some iPods that are not compatible. The shuffles are the worst for compatibility regardless if you are running the latest firmware or not.
As others will confirm on here, the cheapest & easiest way to go is to buy a memory stick. I am a lifetime Apple user and rather than use my iPod Touch in the CTS (yes, it works fine, but I fear leaving it in a hot car in Florida), I bought a Crucial Gizmo memory stick. It works great & cost $22.
Ooops... I meant to add iPod Mini and other older iPods - my former iPod 3G wouldn't work either. Think if it's at least 2 years old, regardless of the firmware, it won't work. Some time ago, I read an article about iPods saying they really are only made to last 2-3 years. Apple has the ability to manufacture them to last longer, but then Apple wouldn't sell new iPods