Anyone able to help?

I'm trying to identify which pins (pads) correspond to which position (sleeve, ring, tip, etc) on a 3.5 mm headphone / microphone jack. I'll post several pics. The cct board is from a Sound Blaster Play 3 - USB sound card. Image of the complete card, closeup of the 3.5mm female jack, then the same spot with the female jack removed. The jack was stupidly destroyed upon removal...newbie.

Any help is appreciated

PS The bottom left pin is ground (assuming sleeve).

 

Solved for headphone.

 

WhatI have seen elswhere is four connections, tip, ring, sleeve, and the back of the sleeve.
"TIP" would be the left channel, ring , the right channel, sleeve would be the common, and the back end of sleeve the microphone.
BUT I might have the sleeve and back of sleeve reversed, with the back end of th sleeve being the common. THAT does make more sense. If that is how it can be verified I hope that somebody will let us know.
"THANKS"

 

Of course it might also be that the scheme is intentionally goofed up so that it would be incompatible with everything else.

 

The sleeve tip and ring I’ve managed to confirm 100% just through trial and error (posted in the last pic). Sleeve bottom left, ring top left, tip bottom right. That was enough to get the headphones working. The other two I think are switching for the usb with one one them being a mic input for a combined headset / mic … which I don’t need for my project.

 

Just for context I’m attempting to create an adapter for an aviation headset (Bose a20) to attach through USB to a PC. I’ve got the headphones working fine I’m just tackling a phantom/bias power circuit for the electret microphone.