If you are planning on using the Mame Boy Advance SP Kit without the headphone jack, short the headphone jack pins as per the following photo. If you do not do this, you will have no audio through the speaker.
If you are planning on using the Mame Boy Advance SP Kit without the headphone jack, short the headphone jack pins as per the following photo. If you do not do this, you will have no audio through the speaker.