iPod touch to surround sound speakers issue

I've been holding off on buying an iPod dock for my yamaha receiver (unnecessary expense right now), but I'd still like to hear pandora and my mp3s through my 5.1 surround system via my iPod Touch. The receiver is awesome, it has multiple inputs. The easiest way to make the connection (other than the yamaha dock) is to simply plug a RCA cable that utilizes the earphone jack on the iPod and a red and white (R&L) RCA into the rear of the receiver. This seems to work after toggling to the proper output channel on the receiver, that is until the sound comes out of the speakers. Its not poor quality nor is it distorted, THE PROBLEM IS: it only plays out of the left side front, left side rear, and subwoofer speakers. It ignores the other 3 speakers altogether. I'm perplexed. I've tried changing the settings on the receiver, ie the preprogrammed equalizer settings and surround sound decoder settings to no avail. When I set the stereo to 2 channel I get sound from just the front left speaker if I set it to 7 channel I get sound out of the left front and rear and it sounds louder than when set to any other preset. Is this as simple as the earPhone out only being able to output two speakers worth of sound one for the left ear and one for the right? Thanks for any help and or clarification.