Have a Loewe's 9383B. Am using 3 inputs-set top box-satellite-cable. On set top box the picture is perfect. On the other 2 inputs, the picture is cut off at the bottom, for instance lettering that scrolls at bottom.Can this be corrected, and how do I do it? Also am using samsung 360 Hi def receiver. On set top box there are gray bars. Can they be made black?