I was just speaking with my Dad who said he has been having a couple of issues with an HR23 (unexplained 771B). his set-up: SL3 (3 lnb dish) connected to a SWM-8 (4-wires from dish to SWM)with an HR23-700 and HR22-100. NO OTA, NO DECA Output 1 connected to the PI and then the HR23 Output 2 connected to the HR22 One of the first things I had him do was to check his signal levels. All the levels are fantastic (matter of fact, I wish mine were as good) but when we got to the SWM mode, He mentioned that #8 was a zero. I had him go into the other room and check the levels there and again everything was great except he had a zero on #4 (#8 was 100). I have currently suggested using one of the green 2 way splitters I sent home with him during his last visit and connect both receivers to the same output and terminate the PI ad see if that fixes this odd 771B error. I am not seeing this type of behavior on my system with SWM-16's so my question here is if this is normal behavior or if signs of a failing SWM. I called DirecTV and spoke to a tech on his behalf and there only solution was to reauthorize the system and set-up a service call. FYI, his system has been working perfectly for at least 2 years without a problem. The only change he made was replacing a SD receiver with the HR23 just before Christmas..