回複：can I use PC onboard audio output as source in multi room hom

Checked online and here is the reason why answer is no. speaker out is the one with pre-amp. It may damage  the amplifier. (Use low output may OK, but not right way). Use line out is right way to do. So configure the PC as 5.1 and also connect the line out to whole house amplifier system maybe the right way. I will try it now and will update you soon. Hope my PC is able to provide the 5.1 output and also line out output.