A stranger shade of blue

We have these remotes. They operate plug sockets. You plug in the appliance and switch it off and I by remote. Great for saving energy on the TV that only has 'on' or 'standby'. Great for switching on lamps in dark places with no main light. Great for heaters so you don't have to get out of bed. Great for lazy people who don't want to get off the sofa. Sometimes they go crazy and mix frequencies - the light downstairs goes off and the TV upstairs comes on (whilst the light is refusing to respond to remote tapping)! You come to bed to find the room in an eerie blue glow!