Sprinkler Controller AC Adapter Hums

I just received and installed the sprinkler controller which seems to be working fine. However, the provided AC Adapter has a rather noticeable hum to it when plugged in. Is this normal?

Mine does it too but it’s in my garage so it doesn’t bother me lol I can only hear it when I’m next to it.

Thanks for the feedback. I guess then it’s probably normal.

Mine does only when a zone comes on. It’s outdoors, but it still bugs me. I am going to look for a smaller 24v inverter anyway though because it’s also so chunky it blocks both outlets. I’ll post if I find a better option for cheap on Amazon.