Lg G Pro 2 D838 - Phone not detecting headphones (HELP)

Weird thing started happening to my phone... When I plug in a pair of headphones (with or without mic) the phone does not detect that they are plugged in! Sound always comes out of the speakers. I've used apps like SoundAbout to force sound through the headset jack and it seems to do the trick but I'm still trying to find a proper solution for this problem.

The odd thing is that if I turn off my phone, plug in a pair of headphones, and then turn my phone back on, once booted the phone will recognize that it has a pair of headphones plugged in and everything will be fine. It doesn't work when I unplug and try to replug. It only detects the headphones on boot.

1) Is there a solution to this?

2) Anyone know something about mechanics of the 3,5mm jack? How all of this works? It seems that on boot it always tries to check if headphones are plugged in but I suppose that something mechanical in the headphone jack must trigger the check after boot...

3) I have cleaned the jack properly so dirt is not a problem. I have also tried different headphones and none of them are detected.

4) I think that problem is not software related. I have booted my phone in Safe Mode and problem is still there.

If anyone have some suggestion please help!

Thanks in advance.

Sent from my LG-D838