My partner's Mom is insisting that every tv program is a repeat and she's seen it before. She is blaming us for this. Advice?

It began with the Soaps, which she used to love, and now she's refusing to watch them. Now it is every TV programme and she thinks her granddaughter has caused the tv to repeat all programmes. She is adamant she is right. We have gone along with it and had the tv repair people out twice, and now she is getting very agressive about this issue and we can't distract her.