your receiver MUST have 5.1 input. that would be weird if it didnt. how do they expect you to play a 5.1 source when you dont have a 5.1 input. and more inportant a digital output but no input..........

look over the unit very carefully im sure there is a input. make sure you are reading the lines properly on the back. like if it says output and it goes around both then they are both output. if it goes around one and then breaks the other is probably input.

if you have the manual look at that. and if you could look at the front and get the make number and post it in here that would help alot