Top bottom black bars when using HDMI



I have a Samsung HLR 6168W and a LG LDA-531 connected using HDMI. When
I played Widescreen movies in the past, it will fill the whole screen.
Recently (I think after a power failure) I have started seeing black
bars on top and bottom when I play the same DVDs. I cannot get it to
auto stretch in HDMI mode any more. Any help will be most appreciated.

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