Though the fix for this particular issue has remained unchanged for some time now - which can be surprising because it is so un-elegant - this issue continues to come to us from iPhoneFAQ readers. It also continues to pop up on Apple's iPhone discussion forums and on other iPhone related websites. So, we figured we'd publish the all-too-uninteresting solution.
For those unfamiliar with the issue, on occasion, the iPhone will stop outputting sound out of its external speaker after headphones are removed from the headphone jack . Essentially, the iPhone thinks the headphones are still connected and will continue to ouput sound only through the headphone port until you're able to "convince" it that the nothing is plugged in. Often, even powering down and back up one's iPhone won't solve the problem.
Why? Because that attempted solution is just too fancy. Believe it or not, the only known fix to this issue is to repeatedly insert and remove a device from the headphone jack. Remember to play a song or otherwise output sound when plugging and unplugging your earbuds, headphones, etc.
We've forwarded this solution to everyone who has written in with this same issue, and we've yet to hear back from anyone reporting that it did not solve the problem.
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I have had this problem twice. I sent my iphone back to apple and in three days got a brand new phone. And i mind you, this happened twice. Two new phones, same issue. So i recomened given Apple a call if your battery is not so good and you have this problem
I've had this happen to my Samsung A940, my Iphone, and my new Asus Eeepc. I think it is either something in the air or happens to lots of gadgets. The only fix for all is put the plug back into the jack and then pull it back out again. Works for them all.
had the same problem. the real cure is to slice a milimeter circumference off the rubber tubing on the headphone jack so that more of the metal jack is slightly exposed. i know this sounds silly but trust me it works.
well i never had sound on my iphone without earplugs or usbcable connected with the computer.. and even with the ' trick ' from in-out it didn't work
I have had my iPhone for a few months now and this is the first problem I have had with it so far. I went to an Apple store and they fixed the problem immediatly by spraying compressed air into the earbud jack. They used an extension that looked like a earbud jack, but it had small holes placed throughout the extension and then hooked up the compressed air hose to the end of the jack and let er rip. He then reset the phone and everything began running normally.
I tried to plug and unplug the headphone a lot of times after I read your advise and it didn't work for me, but I just turned the iphone off (red slide button) and turned it back on and it worked. I don't know if this is a battery issue, but if it happens again, I will go to apple store and check my battery out. I don't think that it would be a smart move to turn it on and off all the time (if this happen quite often).
Good luck!
I had this problem too but I decided to take a look inside the headphone jack and there was a small piece of aluminum stuck inside possibly from my allergy pills that was tricking the phone into thinking the headphones where still connected. Not saying this is your problem but try and look inside and see if anything is in there causing interference.