9 years ago (the last time I bought I rice cooker) I got a middle of the road Panasonic rice cooker. It was silent. The one I bought before that was silent. Every rice cooker I've never owned since the 80s was silent. All the ones my friends had when I visited their homes were silent.
So, this time I also just picked a middle of the road Panasonic rice cooker only to find out they are no longer silent.
Apparently nearly all the rice cookers are now IH (Induction Heating) and so they need a fan to circulate the air. Panasonic doesn't even make any non IH rice cookers in 2016.