diff --git a/lib/grammar.js b/lib/grammar.js
index d8178e8..5a20da9 100644
--- a/lib/grammar.js
+++ b/lib/grammar.js
@@ -159,9 +159,10 @@ var grammar = module.exports = {
     },
     {
       // a=msid:0c8b064d-d807-43b4-b434-f92a889d8587 98178685-d409-46e0-8e16-7ef0db0db64a
-      name: 'msid',
-      reg: /^msid:(.*)/,
-      format: 'msid:%s'
+      push: 'msid',
+      reg: /^msid:([\w-]+)(?: ([\w-]+))?/,
+      names: ['id', 'appdata'],
+      format: 'msid:%s %s'
     },
     {
       // a=ptime:20
diff --git a/test/jsep.sdp b/test/jsep.sdp
index b951b48..7dbcfe5 100644
--- a/test/jsep.sdp
+++ b/test/jsep.sdp
@@ -8,7 +8,7 @@ m=audio 56500 UDP/TLS/RTP/SAVPF 96 0 8 97 98
 c=IN IP4 192.0.2.1
 a=mid:a1
 a=rtcp:56501 IN IP4 192.0.2.1
-a=msid:47017fee-b6c1-4162-929c-a25110252400 f83006c5-a0ff-4e0a-9ed9-d3e6747be7d9
+a=msid:- f83006c5-a0ff-4e0a-9ed9-d3e6747be7d9
 a=sendrecv
 a=rtpmap:96 opus/48000/2
 a=rtpmap:0 PCMU/8000
@@ -35,6 +35,7 @@ a=rtcp:56503 IN IP4 192.0.2.1
 a=mid:v1
 a=bundle-only
 a=msid:61317484-2ed4-49d7-9eb7-1414322a7aae f30bdb4a-5db8-49b5-bcdc-e0c9a23172e0
+a=msid:93e8b9bb-ad32-417e-9d2d-42c215f50713 f30bdb4a-5db8-49b5-bcdc-e0c9a23172e0
 a=sendrecv
 a=rtpmap:100 VP8/90000
 a=rtpmap:101 rtx/90000
diff --git a/test/normal.sdp b/test/normal.sdp
index e8a5315..b6db40a 100644
--- a/test/normal.sdp
+++ b/test/normal.sdp
@@ -6,6 +6,7 @@ c=IN IP4 203.0.113.1
 a=ice-ufrag:F7gI
 a=ice-pwd:x9cml/YzichV2+XlhiMu8g
 a=fingerprint:sha-1 42:89:c5:c6:55:9d:6e:c8:e8:83:55:2a:39:f9:b6:eb:e9:a3:a9:e7
+a=setup:actpass
 m=audio 54400 RTP/SAVPF 0 96
 a=rtpmap:0 PCMU/8000
 a=rtpmap:96 opus/48000
diff --git a/test/parse.test.js b/test/parse.test.js
index 47e3ee0..8b21f48 100644
--- a/test/parse.test.js
+++ b/test/parse.test.js
@@ -365,10 +365,16 @@ test('jsepSdp', function *(t) {
     'ssrc-group'
   );
 
-  t.equal(video.msid,
-    '61317484-2ed4-49d7-9eb7-1414322a7aae f30bdb4a-5db8-49b5-bcdc-e0c9a23172e0'
-    , 'msid'
-  );
+  t.equal(video.msid, [
+    {
+      id: '61317484-2ed4-49d7-9eb7-1414322a7aae',
+      appdata: 'f30bdb4a-5db8-49b5-bcdc-e0c9a23172e0'
+    },
+    {
+      id: '93e8b9bb-ad32-417e-9d2d-42c215f50713',
+      appdata: 'f30bdb4a-5db8-49b5-bcdc-e0c9a23172e0'
+    }
+  ], 'msid');
 
   t.ok(video.rtcpRsize, 'rtcp-rsize present');
   t.ok(video.bundleOnly, 'bundle-only present');
@@ -975,4 +981,4 @@ test('ts-refclk-sess', function *(t) {
   t.ok(sessTsRefClocks && sessTsRefClocks.length == 1, 'got one TS Ref Clock at Session Level');
   t.equal(sessTsRefClocks[0].clksrc, 'ntp', 'NTP Clock Source');
   t.equal(sessTsRefClocks[0].clksrcExt, '/traceable/', 'traceable Clock Source');
-});
\ No newline at end of file
+});