Controlled residential ventilation - You can hear every word in the other room - Is this normal?

Did you have to cheer up the silencers or are they normally included?

For us, everything was included.

Best regards
Sabine

First of all, thank you for the many replies. Yes, it is really strange. But it definitely comes through the pipes. Through the exhaust air valve very strongly, every word audible. Even in the upstairs bathroom still clearly audible. Through the supply air it comes muffled. But of course, it is very annoying if there is no peace in the children's rooms. And the noise of the ventilation system is also transmitted from the utility room to all rooms. Here are photos: the first shows the exhaust air valve in the kitchen. The others are from the utility room.

Here again two from the utility room, the pipe from the kitchen splits and leads once to the guest bathroom and once to the device

Ah ok you have the variant "Reihenschaltung". Yes, in this case the sounds can be transmitted very well.

Telephone echo suppressors between the rooms are necessary.

I would ask if anything has been installed there.

Even the freely hanging metal pipe conducts quite a bit. With the systems commonly known here, the plastic is cast in concrete or under the screed. I believe the flexible pipes on the device have sound-dampening properties, but as mycraft wrote, that probably is not enough.

Tomorrow someone from the executing company will come by. Is it standard that the [Schalldämpfer] are installed? No one ever pointed out to us that this could happen, and the people from the company also immediately said on the phone that it can't be... Can these [Schalldämpfer] be retrofitted without any problems?