I have cable, no satellite or aerial actually needed, even then I still on the odd occasion get a sharp breakdown and freezing of picture and sound, so the problem obviously is down to the strength of signal being sent from the supplier.
As for Freeview or any other other type of signal strength, one of the posts says the mast is very close, this in fact can actually have a adverse effect and give you too strong a signal, so you would have to use a "Attenuator" to drop the signal strength to get a decent quality.
(You can also sometimes achieve this by wrapping "one or two" strands of the coax outer cable sheath onto the center core cable)
A friend of mine lives in Sutton Coldfield with the mast at the bottom of their road and the picture quality from that site is dreadful, so they get their signal from a different mast.