It's not as far back as the early 90's, but it seems to have some similarities with the early 2000's TV series "Threshold"
The series stars Carla Gugino as Dr. Molly Caffrey, a high-level government crisis management consultant from the Blackwood Institute whose job is to create contingency plans for use in emergencies ranging from natural disasters to nuclear war. In order to have "all bases covered", one of her plans, code-named Threshold, is developed for dealing with the unlikely eventuality of first contact with aliens. One night, the crew of a U.S. naval vessel encounters a UFO. Many crew members subsequently die horribly, but some escape. After the ship is discovered with dead crew members and a videotape of the encounter, the Threshold protocol is activated.
Threshold learns that the aliens are attempting to rewrite the DNA of the human race using, in part, an audio signal that somehow alters some people's body chemistry in such a way that they become alien themselves. Central to all this is a fractal triskelion pattern that keeps appearing – in electronic signals, blood, and even the pattern made by city lights.