Apologies for the lack of information, but over 15 years ago I saw a film on late night TV, and desperately want to know what it was to watch it again! All I remember is as follows:-

It opens in a totally white room, with a white record playing. The main character, a cop, is trying to catch a killer, and he himself is a target. This white room is a reoccurring dream he is having. In the film, at one point he opens his front door and it is rigged with a shotgun to kill him, and at one point he gets in his car and a cassette from the killer plays, taunting him, and the cassette contains a magnet which wipes the message after it plays. The twist is that it turns out he is the killer too, and it is a multiple personality disorder.

Anyone got any ideas? Thanks in advance!