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diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-channelmergernode-interface/audiochannelmerger-input.html b/testing/web-platform/tests/webaudio/the-audio-api/the-channelmergernode-interface/audiochannelmerger-input.html
new file mode 100644
index 0000000000..66a70dcb3b
--- /dev/null
+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-channelmergernode-interface/audiochannelmerger-input.html
@@ -0,0 +1,113 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>
+      audiochannelmerger-input.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/merger-testing.js"></script>
+  </head>
+  <body>
+    <script id="layout-test-code">
+      let audit = Audit.createTaskRunner();
+
+      // Task: Check if an inactive input renders a silent mono channel in the
+      // output.
+      audit.define('silent-channel', (task, should) => {
+        testMergerInput(should, {
+          numberOfChannels: 6,
+
+          // Create a mono source buffer filled with '1'.
+          testBufferContent: [1],
+
+          // Connect the output of source into the 4th input of merger.
+          mergerInputIndex: 3,
+
+          // All channels should contain 0, except channel 4 which should be 1.
+          expected: [0, 0, 0, 1, 0, 0],
+        }).then(() => task.done());
+      });
+
+
+      // Task: Check if a stereo input is being down-mixed to mono channel
+      // correctly based on the mixing rule.
+      audit.define('stereo-down-mixing', (task, should) => {
+        testMergerInput(should, {
+          numberOfChannels: 6,
+
+          // Create a stereo buffer filled with '1' and '2' for left and right
+          // channels respectively.
+          testBufferContent: [1, 2],
+
+          // Connect the output of source into the 1st input of merger.
+          mergerInputIndex: undefined,
+
+          // The result of summed and down-mixed stereo audio should be 1.5.
+          // (= 1 * 0.5 + 2 * 0.5)
+          expected: [1.5, 0, 0, 0, 0, 0],
+        }).then(() => task.done());
+      });
+
+
+      // Task: Check if 3-channel input gets processed by the 'discrete' mixing
+      // rule.
+      audit.define('undefined-channel-layout', (task, should) => {
+        testMergerInput(should, {
+          numberOfChannels: 6,
+
+          // Create a 3-channel buffer filled with '1', '2', and '3'
+          // respectively.
+          testBufferContent: [1, 2, 3],
+
+          // Connect the output of source into the 1st input of merger.
+          mergerInputIndex: undefined,
+
+          // The result of summed stereo audio should be 1 because 3-channel is
+          // not a canonical layout, so the input channel 2 and 3 should be
+          // dropped by 'discrete' mixing rule.
+          expected: [1, 0, 0, 0, 0, 0],
+        }).then(() => task.done());
+      });
+
+
+      // Task: Merging two inputs into a single stereo stream.
+      audit.define('merging-to-stereo', (task, should) => {
+
+        // For this test, the number of channel should be 2.
+        let context = new OfflineAudioContext(2, 128, 44100);
+        let merger = context.createChannelMerger();
+        let source1 = context.createBufferSource();
+        let source2 = context.createBufferSource();
+
+        // Create a DC offset buffer (mono) filled with 1 and assign it to BS
+        // nodes.
+        let positiveDCOffset = createConstantBuffer(context, 128, 1);
+        let negativeDCOffset = createConstantBuffer(context, 128, -1);
+        source1.buffer = positiveDCOffset;
+        source2.buffer = negativeDCOffset;
+
+        // Connect: BS#1 => merger_input#0, BS#2 => Inverter => merger_input#1
+        source1.connect(merger, 0, 0);
+        source2.connect(merger, 0, 1);
+        merger.connect(context.destination);
+        source1.start();
+        source2.start();
+
+        context.startRendering().then(function(buffer) {
+
+          // Channel#0 = 1, Channel#1 = -1
+          should(buffer.getChannelData(0), 'Channel #0').beConstantValueOf(1);
+          should(buffer.getChannelData(1), 'Channel #1').beConstantValueOf(-1);
+
+          task.done();
+        });
+      });
+
+
+      audit.run();
+    </script>
+  </body>
+</html>