Yeah its this one. Yeah, it looks like a TRS, but it seems that the connections are not standard.
If I Plug it in the 3,5mm it wont work. I have to pull it out a bit. Thats what I meant with "the mic only works if i plug it in for about 3/4". If its plugged in fully it wont work.
//Edit: I tried it wit the Onboard Soundcard, an cheap USB Soundcard, and with the new Sharkoon DAC + TRRS-> 2x TRS. Non of them work.