when the wii is turned on, does your screen have miscolored areas? and do flashes persist after the pins fall in bowling?

When the wii is turned on, we notice some miscolored areas on the tv screen - they are a little duller than the surrounding areas. And, when we're bowling, after the initial flashes when the pins fall, there seem to be random lingering flashes in the same general area on the screen. These anomalies don't show up when the wii is not turned on - i.e., when we're watching tv or using another game system.