poor audio from meeting room to remote Zoom users

[Burnhaven]

We're using  a conference device with numerous microphones and cameras to combine users in a physical meeting room with remote zoom users.   The only problem is occasional bad audio from the meeting room to remote users.   Audio between remote users is fine and audio from remote users to the room is fine. Video is always fine.
This problem comes and goes but may exist for 30 minutes or more.
We have no option but to use Wifi at the physical building.    Does this sound like substandard wifi at the building  ( church)  , router configuration necessary , or other?