Artwork does not download and show on player

I have gone through settings probably more than 100 times but artwork or download artwork is in the on position yet it does not show up the artwork? Once in a blue moon or once in awhile it does show up artwork but then goes away on next track. If I try another station from the same server their artwork comes through just fine. If anybody can shine any light on why this is happening I would very much appreciate it I love this program and have been using it as long as I can remember. This is the only problem that I know of. Thanks for any help.