diff --git a/dom/media/test/eme.js b/dom/media/test/eme.js
index 12032f11c776..64d2217e52cf 100644
--- a/dom/media/test/eme.js
+++ b/dom/media/test/eme.js
@@ -332,6 +332,11 @@ function SetupEME(test, token, params)
     });
   }
 
+  function streamType(type) {
+    var x = test.tracks.find(o => o.name == type);
+    return x ? x.type : undefined;
+  }
+
   // All 'initDataType's should be the same.
   // null indicates no 'encrypted' event received yet.
   var initDataType = null;
@@ -353,8 +358,8 @@ function SetupEME(test, token, params)
       var options = [
          {
            initDataType: ev.initDataType,
-           videoType: test.type,
-           audioType: test.type,
+           videoType: streamType("video"),
+           audioType: streamType("audio"),
          }
        ];
       var p = navigator.requestMediaKeySystemAccess(KEYSYSTEM_TYPE, options);
diff --git a/dom/media/test/manifest.js b/dom/media/test/manifest.js
index 94991a0e0f0f..bdcdefa34b7e 100644
--- a/dom/media/test/manifest.js
+++ b/dom/media/test/manifest.js
@@ -792,7 +792,6 @@ var gEMETests = [
   },
   {
     name:"400x300 audio&video tracks, each with its key",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -824,7 +823,6 @@ var gEMETests = [
   },
   {
     name:"640x480@624kbps audio&video tracks, each with its key",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -856,7 +854,6 @@ var gEMETests = [
   },
   {
     name:"640x480@959kbps audio&video tracks, each with its key",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -888,7 +885,6 @@ var gEMETests = [
   },
   {
     name:"640x480 then 400x300, same key (1st) per track",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -921,7 +917,6 @@ var gEMETests = [
   },
   {
     name:"640x480 then 400x300, same key (2nd) per track",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -954,7 +949,6 @@ var gEMETests = [
   },
   {
     name:"640x480 with 1st keys then 400x300 with 2nd keys",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -988,7 +982,6 @@ var gEMETests = [
   },
   {
     name:"400x300 with 1st keys then 640x480 with 2nd keys",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1022,7 +1015,6 @@ var gEMETests = [
   },
   {
     name:"640x480@959kbps with 1st keys then 640x480@624kbps with 2nd keys",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1056,7 +1048,6 @@ var gEMETests = [
   },
   {
     name:"640x480@624kbps with 1st keys then 640x480@959kbps with 2nd keys",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1090,7 +1081,6 @@ var gEMETests = [
   },
   {
     name:"400x300 with presentation size 533x300",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1122,7 +1112,6 @@ var gEMETests = [
   },
   {
     name:"400x300 as-is then 400x300 presented as 533x300",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1156,7 +1145,6 @@ var gEMETests = [
   },
   {
     name:"400x225",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1187,7 +1175,6 @@ var gEMETests = [
   },
   {
     name:"640x360",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1218,7 +1205,6 @@ var gEMETests = [
   },
   {
     name:"400x225 then 640x360",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1252,7 +1238,6 @@ var gEMETests = [
   },
   {
     name:"640x360 then 640x480",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
     tracks: [
       {
         name:"audio",
@@ -1289,7 +1274,8 @@ var gEMETests = [
 var gEMENonMSEFailTests = [
   {
     name:"short-cenc.mp4",
-    type:"video/mp4; codecs=\"avc1.64000d,mp4a.40.2\"",
+    audioType:"audio/mp4; codecs=\"mp4a.40.2\"",
+    videoType:"video/mp4; codecs=\"avc1.64000d\"",
     duration:0.47,
   },
 ];
diff --git a/dom/media/test/test_can_play_type_mpeg.html b/dom/media/test/test_can_play_type_mpeg.html
index f9e410739962..19c574bfba99 100644
--- a/dom/media/test/test_can_play_type_mpeg.html
+++ b/dom/media/test/test_can_play_type_mpeg.html
@@ -69,6 +69,8 @@ function check_mp4(v, enabled) {
   check("audio/x-m4a; codecs=\"mp4a.40.2\"", "probably");
   check("audio/x-m4a; codecs=mp4a.40.2", "probably");
 
+  check("audio/mp4; codecs=\"mp4a.40.2,\"", ""); // Invalid codecs string
+
   // HE-AAC v1
   check("audio/mp4; codecs=\"mp4a.40.5\"", "probably");
   check("audio/mp4; codecs=mp4a.40.5", "probably");
diff --git a/dom/media/test/test_eme_non_mse_fails.html b/dom/media/test/test_eme_non_mse_fails.html
index 10d129391399..64e05a1b0548 100644
--- a/dom/media/test/test_eme_non_mse_fails.html
+++ b/dom/media/test/test_eme_non_mse_fails.html
@@ -12,11 +12,12 @@
 <script class="testbody" type="text/javascript">
 var manager = new MediaTestManager;
 
-function DoSetMediaKeys(v)
+function DoSetMediaKeys(v, test)
 {
   var options = [{
     initDataType: "cenc",
-    videoType: test.type,
+    audioType: test.audioType,
+    videoType: test.videoType,
   }];
 
   return navigator.requestMediaKeySystemAccess("org.w3.clearkey", options)
@@ -68,7 +69,7 @@ function TestSetSrc(test, token)
     manager.finished(token);
   });
 
-  DoSetMediaKeys(v)
+  DoSetMediaKeys(v, test)
 
   .then(function() {
     v.src = test.name;
diff --git a/dom/media/test/test_eme_requestKeySystemAccess.html b/dom/media/test/test_eme_requestKeySystemAccess.html
index 4b92fc607f54..e2402c7ce702 100644
--- a/dom/media/test/test_eme_requestKeySystemAccess.html
+++ b/dom/media/test/test_eme_requestKeySystemAccess.html
@@ -202,12 +202,23 @@ var tests = [
     shouldPass: false,
   },
   {
-    name: 'MP4 video container with mp3 and h264 is unsupported',
+    name: 'MP4 video container type with an audio codec is unsupported',
     keySystem: CLEARKEY_ID,
     options: [
       {
         initDataType: 'cenc',
-        videoType: 'video/mp4; codecs="avc1.42E01E,mp3"',
+        videoType: 'video/mp4; codecs="mp3"',
+      }
+    ],
+    shouldPass: false,
+  },
+  {
+    name: 'MP4 audio container type with a video codec is unsupported',
+    keySystem: CLEARKEY_ID,
+    options: [
+      {
+        initDataType: 'cenc',
+        audioType: 'audio/mp4; codecs="avc1.42E01E"',
       }
     ],
     shouldPass: false,
@@ -218,7 +229,7 @@ var tests = [
     options: [
       {
         initDataType: 'cenc',
-        audioType: 'video/mp4; codecs="avc1.42E01E"',
+        videoType: 'video/mp4; codecs="avc1.42E01E"',
       }
     ],
     shouldPass: true,
@@ -235,7 +246,7 @@ var tests = [
     shouldPass: false,
   },
   {
-    name: 'MP4 video container with constrained baseline h.264 and AAC-LC',
+    name: 'MP4 video container with both audio and video codec type in videoType',
     keySystem: CLEARKEY_ID,
     options: [
       {
@@ -243,7 +254,7 @@ var tests = [
         videoType: 'video/mp4; codecs="avc1.42E01E,mp4a.40.2"',
       }
     ],
-    shouldPass: true,
+    shouldPass: false,
   },
   {
     name: 'MP4 audio and video type both specified',