I renew the question of whether silencers are installed. That conversations from supply air rooms can be heard in exhaust air rooms strikes me as rather strange. The common connection point of these rooms goes back to the ventilation unit.
I don't know if silencers are installed. I once heard that they are available as an optional feature for [decentralized ventilation]. But apparently nothing or nothing correctly was installed here either, if that is not the case for all of you.
Where should silencers normally be installed? We only have silencers in the supply air of the bedrooms, but not in the supply air for the living room, dining room, or office.
Silencers would be clearly visible all around the central controlled residential ventilation system in the technical room. They look like oversized exhaust systems. Without silencers, I am already aware that you have sound transmissions between the rooms.
We have silencers in the exhaust air of the kitchen and bathrooms and of course exhaust air to the outside. In the supply air into the rooms there is a separate duct each, which are soundproofed via the distributors.