check if null to prevent error

bigbluebutton-html5/app/client/views/chat/chat_bar.html

@@ -2,7 +2,6 @@
   <div id="{{id}}" {{visibility name}} class="component">
     <h3 class="title gradientBar">
     <span class="glyphicon glyphicon-comment heading"></span>
-    {{title}}
     {{> extraConversations}}
     </h3>
     {{>tabButtons}} <!-- Display public/options tabs, and private chat tabs -->

bigbluebutton-html5/app/server/redispubsub.coffee

@@ -298,7 +298,7 @@ class Meteor.RedisPubSub
         newSettings = message.payload
 
         # if the disableMic setting was turned on
-        if !oldSettings.disableMic and newSettings.disableMic
+        if !oldSettings?.disableMic and newSettings.disableMic
           handleLockingMic(meetingId, newSettings)
 
         # substitute with the new lock settings