Q: iPhone 6 stuck in headphone mode

I had the same issue After some water splashed on mine. After trying everything possible I found that inside where the jack goes, there are a couple of tiny balls that tell the phone if the headphones are in or out. one of these little balls must have got stuck in and hence the phone thought headphones were in. I used the little key thing that is used to take the sim out, and pushed each little ball a few times. All of a sudden problem solved. Phone back to normal.

iPhone stuck in "headphones" mode

I tried plugging in headphones, that didn't work. Then I went to the Sound settings and messed with the ringer volume (after I restarted the phone) and it started to work hope that helps.

I tried EVERYTHING that I could find in these discussions and what finally worked for me was updating my phone.... So if you have an update waiting try that!

Thank You TimRomanRennie!! I dropped my phone in the toilet and I quickly dried it, but the headphone mode was set on. I tried a hard reset and my phone was due for the new update, still no luck Then I read this suggestion.  I used an air compressor to clean key boards to make sure it was dry and a push pin to tap the little balls in the phone jack. It worked!!

Try this and it works for me...

Setting/General/Accessibility/incoming calls (audio routing for newer software)/set speaker, then headset, then automatic...

it works great on my iPhone 6S.

Tried all the other method...this does the trick for me.  Hope this help you too.

THANK YOU ! Worked perfectly