Quad recording

is this a standard bow with twin tuners or have you installed additional tuner/s?

if its the first, i'd guess is down to your prog A finishing same time as prog C starts? maybe try prog A finish 22:59 then prog C start at 23:00 would be ok? alsdo are you watching something else while these are recording, this may use one of the tuners you might have thought free?

I see you only have 2 tuners available - might be clashing if each is on a separate transponder, and the receiver (as it is usually by default) in the recording settings is set to add a few minutes before and after the scheduled item. If you set this so there is no slack, then it might work, but you might in future miss the beginning or end of each program.