Detecting Input

[souncrd]

Hi all,

I wish to plug my phone in to the RCA input and have it play over speakers connected to the output. However, doing this results in no sound. Playing videos on, say, Youtube works, so I know it's not the output, and the on-board pots are all the way up. What am I missing here?

Also, is there a way to detect whether there is a device connected to the input on the board? Any suggestions on where to start with that?

Thanks, and any help is appreciated!