Using the machine below, when I scan 12648V on Optus D1 I pick up several sky channels but no SBS. I am using a 60cm dish and 10750LNB (basically a sky setup) that I had a friend install for freeview. (I don't have, and never had had sky, however, he is a sky installer).
I get perfect freeview, but cannot get SBS at all. Several neighbours around me using sky dishes get SBS fine with unlocked freeview boxes. One even gets it with his 45cm dish in his housebus!
Nothing else is hooked into the feed cable, only the HTPC. I have made sure no horizontal channels are recording etc.
In MC it tells me I have 100% signal quality when I put the mux and SR in, but i get 6 or 7 encrypted sky channels only.