Help! I've had my GF grill since Christmas and everytime I use it for chicken that's been marinaded, it burns! I try to watch it very closely, but it doesn't seem to matter. It's become the family joke...we sit down to dinner, my husband looks at his chicken with black stripes (not blackened!) and says, "Oh, you've used the George Foreman again!" What am I doing wrong? I know a lot of you use your grills frequently and love them.