Rather than complicated individual purpose systems such as one system for your door access, one system for your communication, one system for your internet, one system for your visual security (CCTV). Why not get systems that can be merged?
Move away from the risk of incompatibility, messy switch over process, variety of hardware settings, fixed single presenter at a time using single cable to projector or TV screen.
Switch over to dynamic discussions and presentations.
Go Podium mode (one user at a time), control by one mediator or
Free Style Group discussion where parties can all show what they mean using their own terminal and own material from where ever the source may be. Be it drop box, corporate server, individual remote terminal, gmail, Internet website, Email or many more sources and share to all in the discussion.