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diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sample-accurate-scheduling.html b/testing/web-platform/tests/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sample-accurate-scheduling.html
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+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sample-accurate-scheduling.html
@@ -0,0 +1,110 @@
+<!DOCTYPE html>
+<!--
+Tests that we are able to schedule a series of notes to playback with sample-accuracy.
+We use an impulse so we can tell exactly where the rendering is happening.
+-->
+<html>
+  <head>
+    <title>
+      sample-accurate-scheduling.html
+    </title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="/webaudio/resources/audit-util.js"></script>
+    <script src="/webaudio/resources/audit.js"></script>
+    <script src="/webaudio/resources/buffer-loader.js"></script>
+  </head>
+  <body>
+    <script id="layout-test-code">
+      let audit = Audit.createTaskRunner();
+
+      let sampleRate = 44100.0;
+      let lengthInSeconds = 4;
+
+      let context = 0;
+      let bufferLoader = 0;
+      let impulse;
+
+      // See if we can render at exactly these sample offsets.
+      let sampleOffsets = [0, 3, 512, 517, 1000, 1005, 20000, 21234, 37590];
+
+      function createImpulse() {
+        // An impulse has a value of 1 at time 0, and is otherwise 0.
+        impulse = context.createBuffer(2, 512, sampleRate);
+        let sampleDataL = impulse.getChannelData(0);
+        let sampleDataR = impulse.getChannelData(1);
+        sampleDataL[0] = 1.0;
+        sampleDataR[0] = 1.0;
+      }
+
+      function playNote(time) {
+        let bufferSource = context.createBufferSource();
+        bufferSource.buffer = impulse;
+        bufferSource.connect(context.destination);
+        bufferSource.start(time);
+      }
+
+      function checkSampleAccuracy(buffer, should) {
+        let bufferDataL = buffer.getChannelData(0);
+        let bufferDataR = buffer.getChannelData(1);
+
+        let impulseCount = 0;
+        let badOffsetCount = 0;
+
+        // Left and right channels must be the same.
+        should(bufferDataL, 'Content of left and right channels match and')
+            .beEqualToArray(bufferDataR);
+
+        // Go through every sample and make sure it's 0, except at positions in
+        // sampleOffsets.
+        for (let i = 0; i < buffer.length; ++i) {
+          if (bufferDataL[i] != 0) {
+            // Make sure this index is  in sampleOffsets
+            let found = false;
+            for (let j = 0; j < sampleOffsets.length; ++j) {
+              if (sampleOffsets[j] == i) {
+                found = true;
+                break;
+              }
+            }
+            ++impulseCount;
+            should(found, 'Non-zero sample found at sample offset ' + i)
+                .beTrue();
+            if (!found) {
+              ++badOffsetCount;
+            }
+          }
+        }
+
+        should(impulseCount, 'Number of impulses found')
+            .beEqualTo(sampleOffsets.length);
+
+        if (impulseCount == sampleOffsets.length) {
+          should(badOffsetCount, 'bad offset').beEqualTo(0);
+        }
+      }
+
+      audit.define(
+          {label: 'test', description: 'Test sample-accurate scheduling'},
+          function(task, should) {
+
+            // Create offline audio context.
+            context = new OfflineAudioContext(
+                2, sampleRate * lengthInSeconds, sampleRate);
+            createImpulse();
+
+            for (let i = 0; i < sampleOffsets.length; ++i) {
+              let timeInSeconds = sampleOffsets[i] / sampleRate;
+              playNote(timeInSeconds);
+            }
+
+            context.startRendering().then(function(buffer) {
+              checkSampleAccuracy(buffer, should);
+              task.done();
+            });
+          });
+
+      audit.run();
+    </script>
+  </body>
+</html>