Beth finds her husband's book and a shot from outside shows her looking at the last few pages in the book. The film cuts back to inside the house and now Beth is looking at the first pages of the book.
Whenever the stereo switches on to show a presence, it plays the same CD. However, the screen on the stereo always shows that FM is selected and it's tuned to 87.4, the starting point of the FM tuning spectrum where no channels exist.
Texts received on different days would have a date separator. Beth's phone seems to indicate he's sending her a text on the same day as the one he died.