Receiver issues in living room (771A)

A brief background:  I know just enough to be dangerous with satellite equipment.

I've had some dealings with tactical SHF in my past, but it's definitely not my forte.

On to the issue:  I have an HD-DVR, an HD receiver, and two SD receivers.  The living room receiver (previously HD-DVR) started to give me a 771A issue (SWM not detected), so I switched out the HD receiver from the master bedroom with the HD-DVR in the living room.  The issue is persistent.  The SD receivers have no issues, no errors are reported.  Once in a while, the HD-DVR in the master bedroom will give me a 771A error and then disappear.

Initially, The 21VDC PI was in the master bedroom and inserted power while the IRD out went to one receiver.  I figured this to be the problem, so I put the PI in the attic where the SWM specific splitter is located, feeding the DC directly to the SWM-LNB, and then out to IRD to the splitter.

This didn't really solve any of the issues in the living room, so I grabbed my multimeter and checked to see what the voltage to the LNB was.  I'm getting around 20.6VDC out of the PI, but not sure how much the power degrades over the COAX to the splitter.  I'm estimating around 75ft from PI to SWM-LNB.  Haven't checked the voltage there yet (though it wouldn't really make sense that the power to the LNB would cause the issue since none of the other receivers have the problem aside from sporadic issues in the MBR.

The living room isn't exactly a home-run type setup, though.  The coax from the SWM splitter runs down to the "basement" (ground level walk out) and into an access panel where the house normally would have the cableco line in.  I ran a gold plated coupler to the line that would typically run to the living room, and I'm fearing the line distance is causing the issue.  I'm not 100% sure, but it could be around 125' or thereabouts.  When first installed, this didn't present any issues and it worked flawlessly for over a year set up like this.

So without further pulling my hair out, could it be the cabling, or the LNB going awry? 

Signal strength from the master bedroom:

101

98 96 96 97 96 100 97 100

97 98 98 99 97 100 98 100

96 100 97 95 98 100 98 100

97 95 97 50 99 100 97 100

99

96 96 94 95 95 95 92 93

95 95 92 92 96 95 n/a n/a

transponders 17-32 are all N/A

103s

0 0 0 72 0 0 N/A N/A

N/A N/A N/A N/A N/A N/A 96 94

0 44 99 96 47 62 82 92

25-32 are N/A

103ca

1-8 N/A

91 84 87 86 85 81 81 88

83 82 82 88 81 82 82 88

25-32 are N/A

103cb

92 94 88 92 87 91 88 92

88 91 89 92 91 92 N/A N/A

17-32 are NA

SWM

100 100 100 97 97 96 96 96

96 N/A N/A N/A N/A N/A N/A N/A

17-32 are N/A

Please note, sorry for formatting.  I had to use the HD-DVR in the master bedroom to get the signal readings because the HD receiver in the living room was picking up signals and then after a few minutes of having signal everything started to drop to zero.  The HD-DVR's tuner 2 is reporting signals fine as well.

For what it's worth, also, even whent the receiver in the living room was getting SOME signal, some of the transponders on 101 would show zero, even though I've verified that the receiver upstairs recorded perfect signal at the same time.

And yes, I've already called to have an appointment scheduled, but I'm quite frankly tired of waiting (appt. on 23rd after already having this issue for a week).  My portable spec any doesn't go any higher than 8.5GHz either so can't peak the dish even if I knew that was the problem. 😞

Thoughts and advice are appreciated.