[mythtvnz] Transponder curiosity

[Noel & Di]

My Mythbox used to run behind a Maxplus receiver, (off it's LNB out).  I 
have now put  it onto a separate dish.  I noticed the CanWest 
transponder didn't get signal lock, but TVNZ transponder did.  Re - 
scanning the two transponders (repeatedly :o// ) I found whichever 
transponder got scanned second, never achieved signal lock. Any Ideas? 
R5F1 and Technisat 2 card. (12483H22500 and 12456H22500)
Noel