Today my cellphone got stuck in headset-mode. I mean really got stuck. Nothing seemed to work (reboots, hard reboots, all the ”standard” trix) .
I found out that there are some switch inside the hole for the headset plug that every now and then gets jammed and keep the phone from understanding that there are no plug in the hole.
So I ended up pouring olive oil on the plug to the headset, then inserting it into the hole, jamming it around a while and removing it. Voila! It worked! You could probably use some other oil, but olive oil was the best I had ^_^
Olive oil on the headset plug.