Isolated AI with no chat whatsoever

Suppose you make a super-intelligent AI and run it on a computer. The computer has NO conventional means of output (no connections to other computers, no screen, etc). Might it still be able to get out /​ cause harm? I’ll post my ideas, and you post yours in the comments.

(This may have been discussed before, but I could not find a dedicated topic)

My ideas:
-manipulate current through its hardware, or better yet, through the power cable (a ready-made antenna) to create electromagnetic waves to access some wireless-equipped device. (I’m no physicist so I don’t know if certain frequencies would be hard to do)
-manipulate usage of its hardware (which likely makes small amounts of noise naturally) to approximate human speech, allowing it to communicate with its captors. (This seems even harder than the 1-line AI box scenario)
-manipulate usage of its hardware to create sound or noise to mess with human emotion. (To my understanding tones may affect emotion, but not in any way easily predictable)
-also, manipulating its power use will cause changes in the power company’s database. There doesn’t seem to be an obvious exploit there, but it IS external communication, for what it’s worth.

Let’s hear your thoughts! Lastly, as in similar discussions, you probably shouldn’t come out of this thinking, “Well, if we can just avoid X, Y, and Z, we’re golden!” There are plenty of unknown unknowns here.