I also use the switch and so far I have not heard any noise.

34 dBA is virtually silence ;) you can't hear that ;)

I know you should never answer a question with a question.
How loud is your PC?

The switch is really not audible in normal operation.
Mine is in the basement and I can't hear it there anyway... But when I put it on and tested it, it was lying 50 cm away from me and I didn't hear any noise either.
So I can really recommend the product when it comes to integration into the Unifi network.