The whole movie was based on airwaves / static showed on TV, that would brainwash/hypnotize viewers to kill others. There was a scene where a couple was sitting on their couch watching TV. I think the TV was showing static of a particular recording, and the wife stood up without saying a word, (i think) went into the kitchen, came back and start stabbing her unsuspecting husband. Then the movie proceed to show more of these examples.
Movie is in English.
The Signal (2007)?
Nope – this movie is likely to be before 2000.
Also, when the wife was killing the husband, she was very stoic… like a machine. That static/recording/show was broadcast, so whoever was watching would start killing