By default, events scheduled in the meeting room calendars will show the name of the organizer instead of the actual event title.
This is a security feature and changing this behavior should be introduced with care. If your organization would like to save subject titles of meetings in the room calendar (So it can be shown on the LoopSign) This is easily fixed through Powershell command.
Please note that all subjects of meetings booked will be visible for everyone unless the meeting is set to private.
To enable subject, run this powershell command:
Get-Mailbox -RecipientTypeDetails RoomMailbox | Set-CalendarProcessing -AddOrganizerToSubject $false -DeleteSubject $false -DeleteComments $false -RemovePrivateProperty $false