Ghost activity or electronic malfunction?

So I work in night shift dispatch for a college. The office is right below a large library that is known to be haunted, jingling keys, whispering, and whistling common auditory phenomena there after hours. The dispatch office is also supposedly haunted, as taps, knocking, and even footsteps and doors opening are sometimes heard. However recently a new more visible phenomena has been seen at the tail end of 2nd shift; the landline phones randomly recieving repeated button inputs despite noone touching or moving it. I have yet to personally witness this, but what i have seen was just a few minutes ago. I went to the restroom and passed a hand dryer on the way to a urinal. I never touched nor even got near it yet as i was doing my business, it turns on. Twice. Again, i am nowhere near it. So i ask y'all, was that just an electrical malfunction possibly caused by the radio i was wearing, or was it a rather hygenic ghosts doing?