IPhone still stuck in headset mode? Try this.

Question

So your iPhone is stuck in headset mode. No sound from earhole speaker, no sound from external speaker unles you use speaker mode during a call. When you change volume, the volume icon says ringer(headphones) even though no headphones are plugged in. Every time you plug in your headphones, the ipod function starts playing songs, and stops when you unplug.
You've tried cleaning the jack. You've looked at previous posts in this forum, and at the knowledgebase.
http://discussions.apple.com/thread.jspa?messageID=6598659
http://support.apple.com/kb/TS1205
http://hackint0sh.org/forum/showthread.php?t=18044
None of these suggestions have helped, and you don't want to hard reset your phone. This is what i think worked for me.
1. Plug in headset when iPhone is locked.
2. Hold down the power button so that the "slide to power off" bar appears.
3. Remove the headphones.
4. Push the "Cancel" button at the bottom of the screen.
5. Go to the phonepad and see if pressing the buttons now produces sound.
(It's possible that I've forgotten something that I did, so the next time my phone locks, I'll try the same method again and update this post. Unless someone else is having the problem and wants to verify.)
~ Matthew Lowe

Answer 1

The root cause is either the presence of lint/dust in the switch or the inadequate resilience of the spring.
Nod, that's the cause of a similar problem, and cleaning the jack tends to help. My problem is a software problem, though, so cleaning and repeatedly inserting the headphones won't help.
With the problem I have, the iphone responds to the headphones being inserted or removed, so it knows they're there (or not there) but it fails to switch the speaker output.