Trouble with audio using PC headphones/mic

Hello~ I’m trying to get headphones with a mic (not a headset) to work on the PS3. I started off following these suggestions and fiddled with it from there and I just can’t get it to work. What I want is for both the game’s audio AND voice chat to come through the headphones, but it seems I can only get one or the other?

These are the headphones I got- Koss SB49

With this audio adapter: Syba USB Stereo Audio adapter

I plugged the microphone jack into the USB adapter, and the adapter into the Playstation. Then I plugged the headphone jack into my stereo. I could hear the game through the headphones, but not my friend’s voice. So I plugged the headphone jack into the USB adapter, and I could hear my friend’s voice through the headphones and the game’s audio from my speakers, which defeats the purpose of the headphones…… sigh. I also tried plugging the headphone jack into the PS3‘s audio cables (luckily had an adapter for that) and that didn’t work either. Aaand I messed with the output settings on "Audio Device Settings" and it didn’t help.

Any suggestions? I’m hoping I can make this work somehow but if not, I’ll return this stuff and get the Ear Force PX1 headphones instead. Thanks in advance!