diff --git a/audiogram/waveform.js b/audiogram/waveform.js
index 47fc0095..fdbf3a77 100644
--- a/audiogram/waveform.js
+++ b/audiogram/waveform.js
@@ -76,7 +76,7 @@ function processSamples(samples, numFrames, samplesPerFrame) {
 
   var adjusted = unadjusted.map(function(frame){
     return frame.map(function(point){
-      return [adjustment * point[0], adjustment * point[1]];
+      return point.map(function(p){ return adjustment * p; });
     });
   });
 
diff --git a/test/probe-test.js b/test/probe-test.js
index 2864cac3..e7b0af2c 100644
--- a/test/probe-test.js
+++ b/test/probe-test.js
@@ -22,6 +22,20 @@ tape("MP3 probe", function(test) {
 
 });
 
+tape("Mono probe", function(test) {
+
+  probe(path.join(__dirname, "data/glazed-donut-mono.mp3"), function(err, data){
+
+    test.error(err);
+    test.equal(typeof data.duration, "number");
+    test.equal(data.channels, 1);
+    test.assert(Math.abs(data.duration - 26.67) < 0.1);
+    test.end();
+
+  });
+
+});
+
 tape("WAV probe", function(test) {
 
   probe(path.join(__dirname, "data/glazed-donut.wav"), function(err, data){
diff --git a/test/waveform-test.js b/test/waveform-test.js
index 689e175a..72b966bc 100644
--- a/test/waveform-test.js
+++ b/test/waveform-test.js
@@ -1,7 +1,8 @@
 var tape = require("tape"),
     path = require("path");
 
-var getWaveform = require("../audiogram/waveform.js"),
+var Audiogram = require("../audiogram/"),
+    getWaveform = require("../audiogram/waveform.js"),
     probe = require("../lib/probe.js");
 
 var sample = path.join(__dirname, "data/glazed-donut.mp3");
@@ -17,18 +18,17 @@ tape("Waveform", function(test) {
 
     test.error(e1);
 
+    options.channels = data.channels;
+    options.numFrames = Math.floor(data.duration * options.framesPerSecond);
+
     getWaveform(sample, options, function(e2, waveform){
 
       test.error(e2);
-      test.assert(Array.isArray(waveform) && waveform.length === Math.floor(data.duration * options.framesPerSecond));
-
-      var firstMax = Math.max.apply(null, waveform[0].map(function(d){ return d[1]; }));
-
-      test.assert(firstMax <= 1);
+      test.assert(Array.isArray(waveform) && waveform.length === options.numFrames);
 
       test.assert(waveform.every(function(frame){
         return frame.length === options.samplesPerFrame && frame.every(function(f){
-          return f.length === 2 && typeof f[0] === "number" && typeof f[1] === "number" && f[0] <= 0 && f[0] >= -1 && f[1] >= 0 && f[1] <= firstMax;
+          return f.length === 3 && f.every(function(d){ return typeof d === "number"; }) && f[0] <= 0 && f[0] >= -1 && f[1] >= 0 && f[1] <= 1 && f[2] >= -1 && f[2] <= 1;
         });
       }));
 
@@ -42,33 +42,43 @@ tape("Waveform", function(test) {
 
 tape("Max Duration Error", function(test) {
 
-  var options = {
-    framesPerSecond: 20,
-    samplesPerFrame: 10,
-    maxDuration: 20
+  var audiogram = new Audiogram("xyz");
+  audiogram.audioPath = sample;
+  audiogram.settings = {
+    theme: {
+      maxDuration: 20
+    }
   };
 
-  getWaveform(sample, options, function(err, waveform){
-
+  audiogram.getWaveform(function(err, waveform){
     test.assert(err);
+    test.assert(err.toString().match(/Exceeds max duration/));
     test.end();
-
   });
 
 });
 
 tape("Max Duration OK", function(test) {
 
-  var options = {
-    framesPerSecond: 20,
-    samplesPerFrame: 10,
-    maxDuration: 30
+  var audiogram = new Audiogram("xyz");
+  audiogram.audioPath = sample;
+  audiogram.settings = {
+    theme: {
+      samplesPerFrame: 10,
+      framesPerSecond: 20
+    }
   };
 
-  getWaveform(sample, options, function(err, waveform){
+  probe(sample, function(err, data){
+    test.deepEqual(Math.round(data.duration), 27);
+    test.deepEqual(data.channels, 2);
 
-    test.error(err);
-    test.end();
+    audiogram.getWaveform(function(waveformErr, waveform){
+      test.error(waveformErr);
+      test.assert(Array.isArray(waveform));
+      test.deepEqual(waveform.length, Math.floor(data.duration * audiogram.settings.theme.framesPerSecond));
+      test.end();
+    });
 
   });