I have had this Toshiba 21 inch LCD TV for almost two years now and lately I have noticed there are grey to black marks that look like big fingerprints on there. I have tried to unplug the TV and clean it with a special soft cloth then plug it back in but the marks are still there. I even tried to unplug for 30seconds and plug back in and they are still there except when I turn the TV off and I don't see them. Anyone know what this could be and if anything can be done about it besides expensive repair and maybe replacing the TV itself? Thanks in advance.