Q: iPhone 4S - Outgoing call no audio

Just went to the Apple Store Today (Genius Bar Appt).

I explained the problems I was having. The guy who was serving me firstly checked the audio jack for fluff and then...

He took my serial number - typed it into a 'diagnostics' page on his store ipod/iphone thing.

He then told me that it looked like a hardware issue and swapped my phone. (a new one in a half size black box). He said that this was a new phone, they would have refurb ones for a while yet, as the 4S is so new still.

Unfortunately my screen is now suffering from the yellowing issue, but at least I can make calls!

Update for me, went to the Genius Bar got a replacement phone and all the issues have gone so far.

In my opinion it is 100% a hardware fault so get the changed ASAP if you have bought within 30days!

My first early 4S had no problems at all buy had a faulty speaker, the replacement which was restored from the same back up had the problems described by the OP and was the same even on the OS5.0.1 update. The 2nd replacement restored from the same software has suffered no issues at all.

I think it's a componnant batch problem on a relatively small number of phones.

I got my 4s in Hong Kong a few days ago and found the same problem with the earphone.  Today when I plugged the earphone for the first time while I was driving, the "handfree" auto came on and I could hear my wife voice....but she could not hear my response.... even I unplug the jack,

While reading this topic and tried to figure out what happed, I managed to power off (long hold power button and slide power off) the unit while the earphone plugged in.....and to my surprise everything went normal.......unit now I am writing this reply.......

Worth a try.

I'm experiencing the same problem too, I've noticed that if I keep the handset at a 45 degrees angle while making the call and then when I get an answear put it back in the proper call position everything is fine

After replacing the handset and having used it for nearly 4 days now, I can confirm that issue does not exist on the new handset. It must be a hardware issue.

I suggest replacing the phone.

How much time apple gives to exchange phones that have issues?

LOL, I also noticed that my replacement seemed to have a lower color temperature screen, more like cloudy white balance on a camera, versus daylight.  I am guessing this will fade over time, perhaps it's because it's so new, the adhesive is still drying or something.  It doesn't bother me that much, it actually seems easier on my eyes than a higher color temperature.

Good thing is that I've made some 40-50 calls, and not had an issue yet.  I for sure think there is some kind of hardware issue that is perhaps a variability issue in some componenet that is causing the problem in only a select few handsets.

Regarding the amount of time to exchange phones with issues, I believe the phone has a 1 year warranty, so anytime within that year, you should be able to get it replaced.  The issue is that they normally replace it with a refurbished phone, but since the 4S is so new, they haven't had a chance to refurbish any, so you are getting a new phone right now.  That may not be the case in a few weeks.

You have 30 days to return for full refund.

I know this is in reference to the 4S, however I experienced the same problem approximately 2 weeks ago 11-04-2011 with my old 3G iPhone with at&t. I had recently used headphones and that may have been the culprit. I was able to use the phone for 2 days with no problems after(conflicting I know,but..) I unpluged the headphones but then the problem came where I was not able to recieve audio from my phone unless I selected speakerphone.  It resovled itself after that.... I hope this helps some of you new 4S users understand that it may not be an issue specifically for the 4S model.

I am having the same audio problem with outgoing calls. I have a white AT&T 64GB iPhone 4S. I tried another user's suggestions of turning off Siri Raise to Speak feature and I will update after I make some calls. In addition the Audio on my Music (iPod) app is not working consistently. It will not output audio on random songs and will sometime not even play a song. The Music App problem didnt start until I upgraded iOS to 5.01.

We'll my "this is totally a software issue" statement appears to be wrong.  I replaced my 4s 2 weeks ago and have yet to be able to reproduce the problem.  I'm in the 'replace the phone within 30 days' camp to fix this issue.

I just exchanged my phone this morning.  As everyone else said, no questions, tests, etc.  They just took my serial number and handed me a new phone.  No problems so far.  If you're going to replace yours, just do a back-up in iTunes first so you can restore from back-up with the new phone.  Easy-peasy.

I do have the Apple Care plan, but it sounds like that isn't even necessary for a replacement for this issue.  If you're worried about making it in before the 28-30 days, call and have them open a trouble ticket (or whatever they call it) so you're issue is already on file when you take it in.  I did need an appointment with a 'genius' to do the switch. 

Good luck, everyone.

Just came back from the Apple store with a new (replacement) phone. No issues as expected, though I did panic in a store when a new phone had no sound on my first outgoing call. Turns out with protective film you can't hear anything. Anyway. To the rest of ya, just go and replace your phone. It does look like a hardware issue. And you don't want to end up in a situation like mine yesterday, where I couldn't call for a car service as every outgoing call of mine (I made 7 of them) was silent. Very frustrating. I think the problem only gotten worse over the time.
So, go and get a replacement. All I needed was a Genius Bar appointment. I've made it on Saturday, Monday I got a new phone. Good luck.

Update, My new iPhone 4s was fed ex'd and arrived today.  It seems to be working perfectly.  Made 6 calls and they all connected. Backed everything up to the iCloud yesterday, so all my stuff was updated instantly.  Pretty easy transition.  Go get a new phone!  Don't wait for them to fix it.  it's too frustrating to keep it - when apple will replace.

Confirmed that this issue persists even after updating to 5.0.1 and resetting network settings.  Appointment set for tonight at Apple Store.  You may want to replace your phone if you are having this problem as it was mentioned earlier in this thread that these phones are failing the diagnostics that Apple is using at the store.