diff --git a/lib/vtt.js b/lib/vtt.js
index 66ab23f..bf0a320 100644
--- a/lib/vtt.js
+++ b/lib/vtt.js
@@ -266,12 +266,12 @@
       // Apply default values for any missing fields.
       cue.region = settings.get("region", null);
       cue.vertical = settings.get("vertical", "");
-      cue.line = settings.get("line", "auto");
+      cue.line = settings.get("line", cue.line || "auto");
       cue.lineAlign = settings.get("lineAlign", "start");
       cue.snapToLines = settings.get("snapToLines", true);
       cue.size = settings.get("size", 100);
-      cue.align = settings.get("align", "middle");
-      cue.position = settings.get("position", "auto");
+      //cue.align = settings.get("align", "middle");
+      cue.position = settings.get("position", cue.position || "auto");
       cue.positionAlign = settings.get("positionAlign", {
         start: "start",
         left: "start",
diff --git a/lib/vttcue.js b/lib/vttcue.js
index d838635..7701821 100644
--- a/lib/vttcue.js
+++ b/lib/vttcue.js
@@ -60,7 +60,7 @@
 
   function VTTCue(startTime, endTime, text) {
     var cue = this;
-    var isIE8 = (/MSIE\s8\.0/).test(navigator.userAgent);
+    var isIE8 = (typeof navigator !== "undefined") && (/MSIE\s8\.0/).test(navigator.userAgent);
     var baseObj = {};
 
     if (isIE8) {
@@ -94,7 +94,8 @@
     var _snapToLines = true;
     var _line = "auto";
     var _lineAlign = "start";
-    var _position = 50;
+    //var _position = 50;
+    var _position = "auto";
     var _positionAlign = "middle";
     var _size = 50;
     var _align = "middle";