Just go my RS SPL meter and all the connectors and various cables. I followed the diagram on this site. I calbrated my sound card already and I tried to calbrate my SPL meter but all it says is LO on the read out. I followed everything the way it says, I ran some of the tests pink noise or whatever its called and I get no sound from any of my speakers or sub. hopefully some one can point me in the right direction.