I had a customer with a similar issue yesterday (upgraded from 1/3 to 2/2). Changed node to duo, ran CS to update 1 hopper went fine, unpacked & installed 2nd hopper, CS comes up No Node & DP switch with 110 on tuner 1, empty tuner 2, 129 on tuner 3. Went back to hopper 1 and after another CS I got 119 on 1, 110 on 2, and 129 on 3. After going round & round, replaced node, LNB, all hopper wiring, etc, I pulled out my outlet tester & multimeter thinking there was a power reversal somewhere. Sure enough there was 38v going over the OUTSIDE of the wiring whenever both hoppers were plugged in. Seeing that I went to remove the ground thinking a backfeed from it to the node. As it turns out, the ground source was actually a 2' steel rod the customer installed on their own while building a new deck (know length because I pulled it out of the ground with 1 hand). 100% reinstall to move to new ground source & the system works fine with no excess voltage.