I told him who I had spoken to the previous time, what had been suggested, and that it hadn't worked. He also didn't think the box was at fault, and said he'd call back. We have now basically given up in disgust over the whole situation. The trouble seems to be that there is no one person they can send who can sort everything out. Granada will be installing a Sky Digital system for us in about 3 weeks.
Customers living on busy roads have many more problems, in our experience.
Picture freezing is common in this circumstance. Seems to work pretty well. Went from signal at 3 on 3 of muxes and sod all on the other 2 up to 5 on the two higher power ones and 4 on the lower powers. Still get minor intermittent interference from one of my light switches, but not as bad as with the set back installation, and RF from the neighbours car ignition seems to be gone altogether. Kevin Me, as they say, too.