If the dish has a Dual lnb and a cable to each STB and one STB wont work on either cable and the other one does, the only other option would be if the LNB power was turned off in that STB or its defective.
If you only have 2 STB's I dont think they install a multiswitch do they?
But even if there is one, if one STB works in either room that would indicate to me its the STB thats crook.
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