I'm gonna have my dad solder a custom cable which connects the left audio tip of one TRS plug to the mic ring of another TRRS plug.
Let me know how it goes. I tried doing the same thing; it didn't work for me.
I just came up with this. It would allow mono headphone sound and two-way communication with maybe an online modem program or something.
Strange and impractical, though.
EDIT: The modem could also be a cell phone with a custom app, or maybe a web page with HTML5 or something like that.
#7✎ 2CarlosEFMLI've made a crossover audio cable, but 3DS doesn't "listen" to it. The trick was a 1k resistor between MIC and GND pins.
-LEFT and RIGHT from PC goes to MIC of 3DS (with 1K resistor to ground)
-LEFT and RIGHT from 3DS goes to MIC of PC
#8✎ 161912Me21Head AdminSecond YearMy account is over 2 years oldWebsiteSyntax HighlighterReceived for creating the code syntax highlighter on SBSNight PersonI like the quiet night and sleep late.Express YourselfDid you connect the grounds together? You might not need the resistor if you do that.
#9✎ 161912Me21Head AdminSecond YearMy account is over 2 years oldWebsiteSyntax HighlighterReceived for creating the code syntax highlighter on SBSNight PersonI like the quiet night and sleep late.Express YourselfUpdate:
I've made my own adapter.
3DS uses LRGM not LRMG
You DO need the resistor between mic and ground. (I think that's how the 3DS detects that there is an external microphone plugged in.)
Make sure there's nothing plugged in to the microphone jack when you plug the adapter in to the 3DS, otherwise it might not detect the microphone.