diff --git a/static/js/controllers/uicontroller.js b/static/js/controllers/uicontroller.js
index fadfe0d9..2113d56e 100644
--- a/static/js/controllers/uicontroller.js
+++ b/static/js/controllers/uicontroller.js
@@ -122,6 +122,7 @@ define(['jquery', 'underscore', 'bigscreen', 'moment', 'sjcl', 'modernizr', 'web
 		$scope.chatMessagesUnseen = 0;
 		$scope.autoAccept = null;
 		$scope.isCollapsed = true;
+		$scope.usermedia = null;
 
 		$scope.setStatus = function(status) {
 			// This is the connection status to signaling server.
@@ -147,7 +148,13 @@ define(['jquery', 'underscore', 'bigscreen', 'moment', 'sjcl', 'modernizr', 'web
 
 		$scope.refreshWebrtcSettings = function() {
 			// Refresh constraints.
-			constraints.refresh($scope.master.settings);
+			constraints.refresh($scope.master.settings).then(function() {
+				var um = $scope.usermedia;
+				if (um && um.renegotiation && um.started) {
+					// Trigger renegotiation if supported and started.
+					um.doGetUserMediaWithConstraints(mediaStream.webrtc.settings.mediaConstraints);
+				}
+			});
 		};
 		$scope.refreshWebrtcSettings(); // Call once for bootstrap.
 
@@ -407,6 +414,12 @@ define(['jquery', 'underscore', 'bigscreen', 'moment', 'sjcl', 'modernizr', 'web
 			alertify.dialog.alert(translation._("Oops") + "<br/>" + message);
 		});
 
+		mediaStream.webrtc.e.on("usermedia", function(event, usermedia) {
+			safeApply($scope, function(scope) {
+				scope.usermedia = usermedia;
+			});
+		});
+
 		appData.flags.autoreconnect = true;
 		appData.flags.autoreconnectDelay = 0;
 
diff --git a/static/js/mediastream/usermedia.js b/static/js/mediastream/usermedia.js
index 8f67c78c..a700472f 100644
--- a/static/js/mediastream/usermedia.js
+++ b/static/js/mediastream/usermedia.js
@@ -126,7 +126,6 @@ define(['jquery', 'underscore', 'audiocontext', 'webrtc.adapter'], function($, _
 
 		this.localStream = null;
 		this.started = false;
-		//this.delay = 0;
 
 		this.peerconnections = {};
 
@@ -253,7 +252,6 @@ define(['jquery', 'underscore', 'audiocontext', 'webrtc.adapter'], function($, _
 		if (!mediaConstraints) {
 			mediaConstraints = currentcall.mediaConstraints;
 		}
-		this.mediaConstraints = mediaConstraints;
 
 		return this.doGetUserMediaWithConstraints(mediaConstraints);
 
@@ -263,6 +261,12 @@ define(['jquery', 'underscore', 'audiocontext', 'webrtc.adapter'], function($, _
 
 		if (!mediaConstraints) {
 			mediaConstraints = this.mediaConstraints;
+		} else {
+			this.mediaConstraints = mediaConstraints;
+			if (this.localStream) {
+				// Release stream early if any to be able to apply new constraints.
+				this.replaceStream(null);
+			}
 		}
 
 		var constraints = $.extend(true, {}, mediaConstraints);
@@ -310,34 +314,48 @@ define(['jquery', 'underscore', 'audiocontext', 'webrtc.adapter'], function($, _
 
 	};
 
-	UserMedia.prototype.onLocalStream = function(stream) {
+	UserMedia.prototype.replaceStream = function(stream) {
 
 		var oldStream = this.localStream;
-		if (oldStream) {
-			oldStream.onended = function() {};
+		if (oldStream && oldStream.active) {
+			// Let old stream silently end.
+			oldStream.onended = function() {
+				console.log("Silently ended replaced user media stream.");
+			};
 			oldStream.stop();
+		}
+
+		if (stream) {
+			// Get notified of end events.
+			stream.onended = _.bind(function(event) {
+				console.log("User media stream ended.");
+				if (this.started) {
+					this.stop();
+				}
+			}, this);
+			// Set new stream.
+			this.localStream = stream;
+			this.e.triggerHandler("localstream", [stream, oldStream, this]);
+		}
+
+		return oldStream && stream;
+
+	};
+
+	UserMedia.prototype.onLocalStream = function(stream) {
+
+		if (this.replaceStream(stream)) {
+			// We replaced a stream.
 			setTimeout(_.bind(function() {
 				this.e.triggerHandler("mediachanged", [this]);
 			}, this), 0);
 		} else {
-			// Let webrtc handle the rest.
+			// We are new.
 			setTimeout(_.bind(function() {
 				this.e.triggerHandler("mediasuccess", [this]);
 			}, this), 0);
 		}
 
-		// Get notified of end events.
-		stream.onended = _.bind(function(event) {
-			console.log("User media stream ended.");
-			if (this.started) {
-				this.stop();
-			}
-		}, this);
-
-		// Set new stream.
-		this.localStream = stream;
-		this.e.triggerHandler("localstream", [stream, oldStream, this]);
-
 	};
 
 	UserMedia.prototype.stop = function() {