The diagram below should help those having trouble connecting the AP-8 to a Prop-1.
Notes:
1) Use P7 for Sio and replace the ULN2803 with the ULN2003 to prevent interference on P7
2) Move the P7 SETUP jumper to UP
3) After recording your audio, move the slot selection DIP switches (0, 1, and 2) to the OFF or OPEN position
-- this looks like Slot 7 is selected; this is what's needed for remote selection of the audio segment
(http://www.efx-tek.com/files/prop-1_ap-8_pir.png)