minor cli error output fix

Author: chrisweb

library/audioDataAnalyzer.js

@@ -129,13 +129,13 @@ analyzer.prototype.getData = function getDataFunction(trackPath, callback) {
 
     ffprobeSpawn.on('error', function(error) {
 
-        if (error === 'Error: spawn ENOENT') {
+        if (error.code === 'ENOENT') {
 
             callback('Unable to locate ffprobe, check it is installed and in the path');
 
         } else {
 
-            callback(error);
+            callback(error.syscall + ' ' + error.errno);
 
         }
 
@@ -328,13 +328,13 @@ analyzer.prototype.getPeaks = function getValuesFunction(trackPath, peaksAmountR
 
             ffmpegSpawn.on('error', function(error) {
 
-                if (error === 'Error: spawn ENOENT') {
+                if (error.code === 'ENOENT') {
 
                     callback('Unable to locate ffmpeg, check it is installed and in the path');
 
                 } else {
 
-                    callback(error);
+                    callback(error.syscall + ' ' + error.errno);
 
                 }