If you have the yellow video cable plugged in from your ps3 to the projector that should produce video out. When you plug the red and white audio cables into the tv (you may need extension cables for the audio rca connections if not long enough) make sure your tv is in the right AV setting and you should hear the audio. If not, connect the red and white audio cables to a speaker or other sound source and you will have sound.

To comfirm, when looking at the chip attached to the heat sink, the pin I have drawn a yellow line from in the diagram (the 3rd long pin in starting from the right hand side (at pin 1) with the heat sink behind the chip - you will notice pin 1 and pin 5 are both long pins forming a total of 6 long pins and nesting adjacent (underneath) each of these long pins are 5 smaller pins forming a total of 11 pins) is DEFINATELY the one you cut if having this no sound through the main speaker issue! It simply means the speakers won’t mute when you plug your headphones into the jack. Please see pin 5 in the diagram below as explained above: