I think in my case the lnb drift issues ARE related to the 129 sat. When ever I had the message, it was while I was running a system information check. IT would have a red X in the slot for 129 and it would say experiencing tuner losses of 3 or 4 on 1 tuner at what ever time and on the other tuner had 4 or 5 tuner losses . I am using a dish 1000.2 with the triple lnb and I got this on both of my dvrs. Clearing the matrix seemed to make it go away.
Yesterday I changed out my dish and repeaked it to get even better signals on 119 and 129 and once again I got the lnb drift issue while running a system information screen and the ReD X in the129 slot. I simply cleared the matrix again like above and then re ran with the cables connected and the problem has gone away.
Also before I did this, I noticed that when I tuned to say 366 FOXSW hd channel that is on 129 sat, I got a black screen. When I checked the strength of the 129 sat on that channel ,it would say transponder 8 /129 satellite locked , 87 strength and then it would say wrong sat in red and default to 105- which I don't have in my matrix. (NOTE THis was after I got L4.03 software.)
I was also getting all of my national hd channels off of the 61.5 side satellite dish I plugged into the triple lnb. After clearing the switch matrix etc, I reran the system information screen and all 4 sats came up green and good. I also checked channel 366 again and this time the DISH HDTV screen was up and music playing. So far no more problems with it.
I think it is all related to the wobbly satellite that is constantly changing positions in space , that is causing the lnb to detect "drift". Maybe they ought to call it "satellite drift" instead of lnb drift.