Phantom noise only heard by remote team

[LAHighwire]

Hi. Occasionally, when a Zoom call is in progress in one of our conference rooms, there is distracting noise. It can sound like glass breaking or water rushing. (At first, I thought it was a live mic on someone's laptop that had not been muted, but that is not the case.) No one in the Zoom conference room hears it. Only participants who are on the call through their laptop in another location. It usually happens multiple times during a meeting, but it may not happen again for a week. We have recorded it in live meetings, but in trying to diagnose, we have recorded hours of Zoom in that room,  it did not replicate. It seems completely random.

I have spoken to many people to find a resolution, but nothing has worked. We even changed out and upgraded our microphones which are now hard-wired into the ethernet cable.

Any suggestions?  Thanks so much!