I watched it probably between 1980ish to 1990ish. A group of people were being menaced by a set of small robots shaped like rectangular prisms that kind of squealed when they moved, like an electric motor spinning up. I remember the robots being taken out via champagne bottles (perhaps they weren't waterproof?) with the character shaking up the bottles and then spraying the robots with the foam.
I'm pretty sure that the robots had been shown to be deadly. I have this vague memory of someone getting cornered by them (a gameskeeper?) and then being shown dead, perhaps via electric shock.