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diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/k-rate-connections.html b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/k-rate-connections.html
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+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/k-rate-connections.html
@@ -0,0 +1,139 @@
+<!doctype html>
+<html>
+  <head>
+    <title>k-rate AudioParams with Inputs</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>
+  </head>
+
+  <body>
+    <script>
+      let audit = Audit.createTaskRunner();
+
+      // Must be power of two to eliminate round-off
+      const sampleRate = 8192;
+
+      // Arbitrary duration that doesn't need to be too long to verify k-rate
+      // automations.  Probably should be at least a few render quanta.
+      const testDuration = 8 * RENDER_QUANTUM_FRAMES / sampleRate;
+
+      // Test k-rate GainNode.gain is k-rate
+      audit.define(
+          {label: 'Gain', description: 'k-rate GainNode.gain'},
+          (task, should) => {
+            let context = new OfflineAudioContext({
+              numberOfChannels: 2,
+              sampleRate: sampleRate,
+              length: testDuration * sampleRate
+            });
+
+            let merger = new ChannelMergerNode(
+                context, {numberOfInputs: context.destination.channelCount});
+            merger.connect(context.destination);
+
+            let src = new ConstantSourceNode(context);
+
+            createTestSubGraph(context, src, merger, 'GainNode', 'gain');
+
+            src.start();
+            context.startRendering()
+                .then(buffer => {
+                  let actual = buffer.getChannelData(0);
+                  let expected = buffer.getChannelData(1);
+
+                  for (let k = 0; k < actual.length;
+                       k += RENDER_QUANTUM_FRAMES) {
+                    should(
+                        actual.slice(k, k + RENDER_QUANTUM_FRAMES),
+                        `gain[${k}:${k + RENDER_QUANTUM_FRAMES}]`)
+                        .beConstantValueOf(expected[k]);
+                  }
+                })
+                .then(() => task.done());
+          });
+
+      // Test k-rate StereoPannerNode.pan is k-rate
+      audit.define(
+          {label: 'StereoPanner', description: 'k-rate StereoPannerNode.pan'},
+          (task, should) => {
+            let context = new OfflineAudioContext({
+              numberOfChannels: 2,
+              sampleRate: sampleRate,
+              length: testDuration * sampleRate
+            });
+            let merger = new ChannelMergerNode(
+                context, {numberOfInputs: context.destination.channelCount});
+            merger.connect(context.destination);
+
+            let src = new ConstantSourceNode(context);
+
+            createTestSubGraph(
+                context, src, merger, 'StereoPannerNode', 'pan', {
+                  testModSetup: node => {
+                    node.offset.setValueAtTime(-1, 0);
+                    node.offset.linearRampToValueAtTime(1, testDuration);
+                  }
+                });
+
+            src.start();
+            context.startRendering()
+                .then(buffer => {
+                  let actual = buffer.getChannelData(0);
+                  let expected = buffer.getChannelData(1);
+
+                  for (let k = 0; k < actual.length; k += 128) {
+                    should(actual.slice(k, k + 128), `pan[${k}:${k + 128}]`)
+                        .beConstantValueOf(expected[k]);
+                  }
+                })
+                .then(() => task.done());
+          });
+
+      audit.run();
+
+      function createTestSubGraph(
+          context, src, merger, nodeName, paramName, options) {
+        // The test node which has its AudioParam set up for k-rate autmoations.
+        let tstNode = new window[nodeName](context);
+
+        if (options && options.setups) {
+          options.setups(tstNode);
+        }
+        tstNode[paramName].automationRate = 'k-rate';
+
+        // Modulating signal for the test node.  Just a linear ramp. This is
+        // connected to the AudioParam of the tstNode.
+        let tstMod = new ConstantSourceNode(context);
+        if (options && options.testModSetup) {
+          options.testModSetup(tstMod);
+        } else {
+          tstMod.offset.linearRampToValueAtTime(context.length, testDuration);
+        }
+
+        tstMod.connect(tstNode[paramName]);
+        src.connect(tstNode).connect(merger, 0, 0);
+
+        // The ref node is the same type of node as the test node, but uses
+        // a-rate automation.  However, the modulating signal is k-rate.  This
+        // causes the input to the audio param to be constant over a render,
+        // which is basically the same as making the audio param be k-rate.
+        let refNode = new window[nodeName](context);
+        let refMod = new ConstantSourceNode(context);
+        refMod.offset.automationRate = 'k-rate';
+        if (options && options.testModSetup) {
+          options.testModSetup(refMod);
+        } else {
+          refMod.offset.linearRampToValueAtTime(context.length, testDuration);
+        }
+
+        refMod.connect(refNode[paramName]);
+        src.connect(refNode).connect(merger, 0, 1);
+
+        tstMod.start();
+        refMod.start();
+      }
+    </script>
+  </body>
+</html>