With my set-up, the
input to my DVD recorder is AV2 (from a Freeview box) and the
output is AV1 (to my TV). Normally I have the recorder set to record AV2.
However - and that's a big 'however', hence the bold - my recorder has the capability to record
whatever is playing on the TV. That's a tricky concept to get your head around, but just remember that Scart cables are bi-directional. So if I set my recorder to record from AV1 (the TV) - and if the TV was set to be 'watching' the secondary output from the Freeview box - it would record exactly the same picture that it would if it was set to record from AV2. However if I did this, it would record nothing but black silence when I turned off the TV.
Yep, just been downstairs and checked it. Set the recorder to AV1, hit record, changed AV sources on the TV a few times, then switched it back to the recorder and played it all back - it played what the TV had been displaying.
Note: Scarts are bi-directional but they can only send signals one way at a time. When I do it this way, the recorder records what's on the TV but it doesn't pass anything back, so .... jeepers this is complicated. You really have to see it to understand it. I can't explain
Does your mother's Sky box have two outputs, one to the TV and one to the recorder? I suspect it does. I suspect that the recorder is set to record whatever's on the AV cable that's connected to the TV, rather than on the AV cable that's connected to the Sky box. If so she just needs to select a different AV source
on the recorder.
One day all this will be easy!
Regards