so instead of plugging the phone to TV RCA why not plug them into receiver RCA? Isn't that what composite audio is (white/red)? Then set your receiver to fake 5.1 out for that input.
I bought a new hdtv and I am trying to get all my stuff connected with the receiver I have. I have my XBOX 360, Blu Ray and HDTV Cable box connected to the back of my tv with 3 HDMI cables. The tv has an optical out so I have an optical cable to my reciever so all those things are in surround sound. I have my desktop connected to the tv with a VGA, the audio is connected from the headphones jack to an auxillary port (RCA). I have some DVD backups on my hard drive and I would like to get the sound instead of standard stereo to be 5.1. The problem is the only port I have left on my older receiver is the composite audio which is an older technology but would give me what I want. I searched everywhere on the internet and the only audio cards I could find have optical out, hdmi, or the computer speakers 5.1 style. I will probably have to get an older card from ebay since this technology is kind of dated but if anyone can point me in the direction of a specific one I would be so very greatful.