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.