This happened to my box also. The problem has been cured by reverting to the machine's original (default) software. To do this, press the menu, Set-up, Help, then press the green button to access the "Advanced Information" page. Then press the yellow button for "software revert".
My box reverted to software v2.93 which has probably lost some of the advanced functionality, but crucially the machine now works whereas it didn't previously.
Lawrence P
December 2009
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