if(!conv.surface.capabilities.has('actions.capability.MEDIA_RESPONSE_AUDIO')) {
          conv.ask('Sorry, this device does not support audio playback.');
        }
        else{
          var mo_list = [
            new MediaObject({
                name: 'Radio one',
                url: 'my_mp3_url_1.mp3',
                description: 'A funky Jazz tune'
            }),
            new MediaObject({
                name: 'Radio two',
                url: 'my_mp3_url_2.mp3',
                description: 'A funky Jazz tune'
            })
          ];
          conv.ask( mo_list );
          conv.ask(new Suggestions(['Radio two']));
        }