iPod classic displays ‘No music’ after sync, HDD problem?

So recently I synced my iPod Classic 160 GB like I did so many times and when I wanted to play some music afterwards it couldn’t find any files on the iPod anymore. However when you look in the settings it displays that ~roughly 90 GB free space is available. Seen the fact that I had about 60 gigs of music this doesn’t seem like a coincidence and I think my music is still somewhere on the ipod but the HDD isn’t recognizing it anymore.

I’ve tried resetting it, and resetting it to factory settings, which didn’t work. When connected to a desktop it won’t be recognized by iTunes, it displays an error message that the iPod cannot be read and that I have to reset it to factory settings.

I’ve spent some time researching this problem yesterday and I ran into a myriad of vaguely similar problems didn’t really offer any help. Currently I’m thinking that formatting the iPod might work, and restoring the software afterwards. However this is a rather bold strategy so I’d like to consult you here first.

Thanks in advance!