Videomaker – Learn video production and editing, camera reviews › Forums › Specialty Topics › Worship Video › Need help with possible static? Displays keep resyncing. › Outside RF transmissions — e
Outside RF transmissions — e.g., a HAM operator who keys his radio from time to time. Some piece of equipment in the hall that generates an electrical connection of some sort — e.g., a furnace that turns on from time to time; air conditioning doing the same; a sump pump, etc. Problems in the hall's electrical circuits at the distribution panel or from connection to the main electrical line.
It is possible — remotely — that a cell phone or similar device is causing this, and equally possible — remotely — that the laptop is at fault.
I wish you well with finding a solution. This is the kind of problem I would typically turn over to an electrical/electronic specialist from the community.