Grunt-connect-proxy, forwarding files does not work

Question

I'm using this library to forward api-request from grunt (port 9000) to my api at node (port 3012). https://github.com/drewzboto/grunt-connect-proxy

It works when the response from the server is a json. But it does not work when it's a image.

I tried to make a proxy with apache and there it works. So it must be something wrong with my proxy in grunt.

This is the response in chrome from apache:

This is the repsonse in chrome from grunt server

The response tab is empty

These are the relevant packages I'm using:

"grunt": "^0.4.1",
"grunt-connect-proxy": "^0.2.0",

This is the proxy in my gruntfile.js

  proxies: [
    {
      context: '/api_paros',
      host: 'localhost',
      port: 3012,
      https: false
    }
  ],

livereload: {
        options: {
          open: true,
          base: [
            '.tmp',
            '<%= yeoman.app %>'
          ],
          middleware: function (connect, options) {
            if (!Array.isArray(options.base)) {
              options.base = [options.base];
            }

            // Setup the proxy
            var middlewares = [require('grunt-connect-proxy/lib/utils').proxyRequest];

            middlewares.push(connect.static('.tmp'));

            middlewares.push(connect().use(
              '/bower_components',
              connect.static('./bower_components')
            ));
            middlewares.push(connect.static(appConfig.app));

            // Serve static files.
            options.base.forEach(function (base) {
              middlewares.push(connect.static(base));
            });

            // Make directory browse-able.
            var directory = options.directory || options.base[options.base.length - 1];
            middlewares.push(connect.directory(directory));

            return middlewares;
          }
        }
      },

Any ideas?