No access to content on my Ipod classic

I can't access any of the content on my Ipod classic. I know it's there because it shows the same amount of used space as before. The only difference is that it looks as if it's in the "other" category as opposed to in the "audio" which is where it should be. With what space is left I can download stuff and have access to it, but I can't get at my music or saved podcasts. Any advice.