I had my power supply replaced....when I got the TV back from the repair shop, all HD channels play stretched out in widescreen letterbox format, for example the station logo is right to the edge of the TV when it should be in the safe title area. That's what I get when I click on the 16x9 option in the picture settings. 4X3 shows seem to playback as normal but I can't say for sure....
I use an HDMI cable from my cable box, cable box is brand new.
Is there something that I am missing, or maybe the power supply failing also affected the main processing circuit board?

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