Turn off the simulator and remove the power plug.
Remove the back cover .
The audio amplifier PCB is located on the bottom of the simulator near the speaker.
Disconnect the audio input , power  and speaker  cables from the audio amplifier PCB.
Squeeze the 4 retaining tabs  to remove the audio amplifier PCB.
Install the audio amplifier PCB and connect the audio input, power and speaker cables.
Note: Make sure the speaker wires  are installed with the correct polarity. The red wire is positive (+) and the black wire is negative (-).
Set the volume knob  to the half volume position. To find the half position, rotate the volume knob all the way to the left then all the way to the right and then set it to the half position.