title: Webpack file-loader serving images but not audio (mp3)
body: <p>I'm writing a TypeScript application using Webpack and file-loader for serving images and audio. I can't get the webpack config to work with audio files.</p>
  
  <p>Im getting <code>GET http://localhost:8080/media/d.mp3 404 (Not Found)</code></p>
  
  <p>The images work fine on the dev server and also build fine with the webpack setup below.</p>
  
  <p>Folder structure:</p>
  
  <pre><code>|-public    
  |---audio    
  |---images    
  |-src    
  |---audio    
  |---images
  </code></pre>
  
  <p>Same result if I combine all extensions into one string and use a single folder.</p>
  
  <p>My <strong>webpack.config.js</strong>:</p>
  
  <pre><code>const path = require('path');
  
  module.exports = {
      entry: "./src/index.ts",
      output: {
          path: path.resolve(__dirname, 'public/scripts'),
          filename: 'bundle.js'
      },
      devtool: "source-map",
      module: {
          rules: [{
                  test: /\.tsx?$/,
                  loader: "awesome-typescript-loader"
              },
              {
                  test: /\.js$/,
                  exclude: /node_modules/,
                  use: {
                      loader: "babel-loader"
                  }
              },
              {
                  test: /\.(scss|sass|css)$/,
                  exclude: /node_modules/,
                  use: ['style-loader', 'css-loader', 'sass-loader']
              },
              {
                  test: /\.(png|jpe?g|gif)$/,
                  use: [
                      {
                          loader: 'file-loader',
                          options: {
                              name: '[name].[ext]',                            
                              outputPath: '../images/',
                              publicPath: 'images/',
                              useRelativePaths: true
                          }
                      }
                  ]
              },
              {
                  test: /\.(mp3|wav)$/,
                  use: [
                      {
                          loader: 'file-loader',
                          options: {                            
                              name: '[name].[ext]',                            
                              outputPath: '../audio/',
                              publicPath: 'audio/',
                              useRelativePaths: true
                          }
                      }
                  ]
              },
          ]
      },
      resolve: {
          extensions: [".webpack.js", ".web.js", ".ts", ".tsx", ".js"]
      },
      devServer: {
          contentBase: path.resolve(__dirname, 'public'),
          publicPath: '/scripts/'
      },
      node: {
          fs: "empty"
      }
  };
  </code></pre>