The housing is not particularly loud. However, it is not very decoupled. In my case, it's on a wooden plate, and that passed on some noise at the beginning. In the meantime, I put 2 cm of rubber under the feet, and since then practically nothing is audible. The fan is quiet enough. You can set 3 levels and there is also an automatic control. If the data transfer is high for hours, the fan gets a little louder (and then audible). After almost 2 years of operation, the fan on one of the two units has become a little louder (bearing) and I will occasionally replace it with a (quiet) replacement fan. I find the enclosure to be sufficiently well constructed and reliable. There have been no failures despite 24/7/365.

I have a question for " denmenschenistderstandabhandengekommen".
I find the fan relatively loud for use in the living room. Have you already replaced it and if so, which fan have you installed?