Please forgive me if this has been covered in the forum already, but I ran a search after registering without any quality results. My Toshiba rear projection TV (about 4 years old) has developed a strong green tint but only on devices plugged into the HD ports. Everything is running normally and clarity isn't an issue. It's like the screen has a green film over it. Using the RCA jacks results in a normal (but non-HD) image. Warranty has expired. Any ideas where I should begin? Thanks.