A humming Lingo

When I power up my Lingo these days, there is a noticable humming noise coming from the unit. I can't really work out if it filters through to play back significantly as I always get a faint buzz from phono anyway even when Lingo is switched off. I know that ideally the Lingo should be left on all the time, but as all my hifi is plugged into one socket I'm trying to save a bit of electricity these days (though not sure how much!)Something to worry about or just ignore it?