diff --git a/dom/media/webaudio/ThreeDPoint.h b/dom/media/webaudio/ThreeDPoint.h
index b6d51e69a32c..71a2dad65523 100644
--- a/dom/media/webaudio/ThreeDPoint.h
+++ b/dom/media/webaudio/ThreeDPoint.h
@@ -36,6 +36,11 @@ struct ThreeDPoint final
 
   void Normalize()
   {
+    // Zero vectors cannot be normalized. For our purpose, normalizing a zero
+    // vector results in a zero vector.
+    if (IsZero()) {
+      return;
+    }
     // Normalize with the maximum norm first to avoid overflow and underflow.
     double invMax = 1 / MaxNorm();
     x *= invMax;
diff --git a/dom/media/webaudio/test/mochitest.ini b/dom/media/webaudio/test/mochitest.ini
index acfdd056e2a6..4345d79cfead 100644
--- a/dom/media/webaudio/test/mochitest.ini
+++ b/dom/media/webaudio/test/mochitest.ini
@@ -100,6 +100,7 @@ tags=capturestream
 skip-if = toolkit == 'android' # bug 1056706
 [test_bug1255618.html]
 [test_bug1267579.html]
+[test_bug1355798.html]
 [test_channelMergerNode.html]
 [test_channelMergerNodeWithVolume.html]
 [test_channelSplitterNode.html]
diff --git a/dom/media/webaudio/test/test_bug1355798.html b/dom/media/webaudio/test/test_bug1355798.html
new file mode 100644
index 000000000000..01909f176b4e
--- /dev/null
+++ b/dom/media/webaudio/test/test_bug1355798.html
@@ -0,0 +1,30 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test PannerNode produces output even when the even when the distance is
+    from the listener is zero, and the cone gain is present, regression test for
+  bug 1355798.</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script type="text/javascript" src="webaudio.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<pre id="test">
+<script class="testbody" type="text/javascript">
+SimpleTest.waitForExplicitFinish();
+var off = new OfflineAudioContext(1, 128, 44100);
+var panner = off.createPanner();
+var osc = off.createOscillator();
+panner.setPosition(1, 1, 1);
+off.listener.setPosition(1, 1, 1);
+osc.connect(panner).connect(off.destination);
+panner.coneOuterAngle = 359;
+osc.start();
+off.startRendering().then(function(b) {
+    is(b.getChannelData(0).filter(x => isNaN(x)).length, 0);
+    SimpleTest.finish();
+});
+</script>
+</pre>
+</body>
+</html>
