Chosen Solution

Ipod was on a seat that was wet for 2 hours. Since then it plays on my B & W Zeppelin but nothinhg happens when trying to play from battery. When attached to a Windows computer it flickers and shows the Apple logo but is not recognised and therefore cannot sync etc. Unable to Rest or place it in Disk Mode

Joe Rowbotham, since it does work from a dock and not from battery or USB port, I’d go ahead and start by replacing the battery. It is possible that your battery is at the end of its lifespan. It will work from the dock since it delivers more amperage than your USB port. Of course, make sure that you also clean the iPod using this guide. Here you can find the instructions iPod Classic Repair to change the battery. Good Luck