Yep, sounds like using both input ports on the HR24 is the problem. That's wrong. As already stated, for one box you only need a dish and a box with the PI in between. For more than one, the PI can be anywhere in the line so long as it is before the splitter or through the red port after the splitter. It cannot be in the elements.
Your SWM LNB sends eight discreet channels down the line that can be split if required to feed up to eight tuners. DVR's have two tuners while Genie's have five. Software figures it all out. Except for the HR20-100 only the Sat 1 input is connected to the SWM dish. ONE feed per box, period.
Some schematics:
SatGuysUS
