This indicates that the MIDI Out settings may be conflicting with the audio.

1. Click on the "Configure MIDI Out" button at the bottom of the screen. 
   This is the second button from the right. 

2. Change the MIDI Out setting from MIDI Mapper to one of the other MIDI 
   outputs available from the sound card.

3. Play a Video. 

4. Once the sound for video is working, double-check to be sure that MIDI 
   is still working. 
   a) From the Main Menu, click "Rumble" and then "Play". 
   b) You should hear the guitar playing.  If you do not, change the MIDI 
      Output port again. The goal is to find the option where you will 
      hear both the Videos playing (audio) and the guitar playing (MIDI).

______________________________________________________________________________