While you are on Lifesize Cloud call via CHROME, and if the call disconnects for unknown reason.
Please helps us collect the logs, before raising a ticket.
Open a new browser tab in Chrome > type > chrome://webrtc-internals/ > Expand Create Dump > click Download the PeerConnection updates and stats data
A log file is download, please attach it to the case.
(NOTE: If the issue is related to Audio, also check "Enable diagnostic audio recordings")