As @borjan stated above: he confirmed that FP2 (only?) supports the CTIA standard.
Still open is, if the FP1 really only support the OMTP, what our experience would suggest? The FP1-specs don’t have any clue about this.
All headsets which do not work properly obviously implement the OMTP standard, where the pin for mic and ground are reversed
(I do not debate, why the world need 2 standards with that minor changes!
And I do not guess, why this was introduced!
But I do ask about, why FP1 and FP2 have different standards?)
So the last missing information is:
Is here any chance that a software-change can do the trick?
Or if CTIA standard is hardcoded in the hardware of the FP2 and cannot be changed (which I fear)?
Can anybody tell my, where at this linked page stands, that OMTP-headset do not work with android, or are even not allowed?
I can only read “OMTP … optional” and “CTIA … required”, but don’t know what this means.
Any help with this?
Is there any argument, why the FP2 should not support the OMTP?
Is it possible to mechanically support CTIA and OMTP at the same jack? (I guess no)