When Dr. Graf is discussing his preliminary findings to Moser, he expresses doubts as to Mrs. Mader's suicide judging by a second set of ligature marks on her neck. As Moser inspects them, we see a close-up of her neck with the bruising he mentioned as well as her pulse beating strongly under the skin.
During the take in the morgue, when Moser and Dr. Leo Graf examine the corpse, in the face close-up, its eyelashes make slight nervous moves.
When inspector Moser talks for the first time with the Riedl couple, a few centimeters of the boom mic quite obviously enter the screen. The mic being black and the wall being beige, it does hit the eye.