iPhone 5 bad call voice quality

Glad to find this thread. It took me a while to figure out what the problem was. On my AT&T LTE iPhone 5 using any Apple earphone audio goes up and down (I never use audio any other way). I'll try the hearing aid fix, though it doesn't help with headphones. I'll also try going off LTE.

At least I know now to to an urgent replacement but I'll go to Apple store to get a date associated with the problem.

Okay, here we go...

Here is my english version to submit your iphone 5 problem:

http://iphone.dominik.de/en

sorry, for my english 🙂

I have simliar problems with my new iPhone 5. I don't know I should go back to 4S or wait till Apple to fix it.

If it is a hardware problem like many advocated here, then Apple has to do a recall?

If they are going to do a recall then maybe I should hang on my iPhone 5 till then? Any advice?

My personal advice for you is that if you are not perfectly happy with your iPhone 5 and you are within your return period, that you return your device before your return period expires. While I am not experiencing this problem, I have my own share of problems and I failed to return my device within the 14 day period because I kept hoping some magical SW update would make my problems all go away and now that it hasn't and I'm beyond my return period, I'm out of luck.

I think you should go into the Apple store at least, get your phone registered as having the problem.

UPDATE:

I changed last week from provider and no more problems.

I'm sure it has to do something with the HD Voice and how the providers are dealing with it.

I'm happy my iphone 5 is working great now.

In some limited testing I've done with my AT&T US iPhone 5 at home and work and in transit I suspect the clipped audio (volume drop out, lost words) may be cell tower related. I did find several reports here that noted things were worse at one location, better at another.

Note that even on LTE networks AT&T audio uses 3G. So if it's cell tower related, it might be something with how AT&T changed its 3G networks when it put in LTE.

That may explain why we have spotty reports in the US but many reports from Austria and Germany -- could be carrier and even tower specific.

This sounds like a real pain to figure out -- too many moving parts and issues. (Note in this discussion group it's clear that many different problems are being discussed, and that some of them are clearly hardware related.)

I'm updating my blog post on this topic as I learn more;

http://tech.kateva.org/2012/12/voice-call-audio-clipping-and-dropouts.html

I do have an Apple Store visit scheduled but I don't think I'll learn much there.

Some interaction between the iPhone 5's HD voice capability and how some carriers are implementing 3G on some towers that also provide LTE...

So a fix might happen with a change to iOS software, or a change to carrier software.

I'm on my 3rd iphone 5 in Chicago. We'll see if this one works. Genius told me there is no widespread issue that he's aware of but he could hear the issue on a test call and that was enough. Also doesn't know if it's hardware or not but he said the software on the phone looked good just like it had on my first phone. Glad they're so cool about switching out the phone. Keeping my fingers crossed. It's not the end of the world so I'm fine with trying out this new phone. Always been an Apple fan. Always will be. In the big scheme of things we're lucky to have these things.

Since iPhone 5 has 3 microphones and if you use the earphone and you stick the iPhone in your pocket, then how in the world the noise cancellation will work?

I'm betting they did not test this scenario well enough and may leave one of the microphone on even there is an earphone plugged in!

In my case, I found the voice call problem is more pronounced with the earphone. And of course, when you are playing any MP3, the sound comes out fine (all the microphones are off totally).

This reasoning gives me hope that this is just a software problem, and no need for a hardware fix.

FWIW I also submitted a report to AT&T and I tried resetting my network settings. I don't think LTE settings make any difference for my voice use (I use a earset)

After researching this issue for 3 days, I concluded that it all comes down to the "new" NOISE CANCELLATION system being implemented on the iPhone 5. The bad voice call quality, the dizziness, the muffled sound, the fading in and out, back ground noise, the useless earphone, etc are all caused by the same problem.

There are several major differences between iPhone 4 and 5 regarding noise cancelling:

1. iPhone 5 has 3 microphones. One or all may be used for noise cancelling. The iPhone 4 has only two microphones. Complexity breeds problems.

2. iPhone 5 has a back-side microphone that may be used for noise cancelling that may be not best located. What if this microphone is blocked or partially blocked or affected by wind noise?

3. the new noise cancellation hardware & software was done by Apple, previously done by Audience, which did works for Google Nexus and Samsumg GS. New hardware & software are likely leading to more bugs.

4. The new earphone that has its own "noise cancelling" may not be thoroughly tested with the iPhone 5. We are not even sure if the microphones on the iPhone are turned off while earphone is plugged in.

5. It seems iPhone 5's noise cancellation system did not make use of promixity sensor to sense whether the person is close the phone or not and adjust its "noise cancelling" accordingly.

In my previous life, I used to work as a telecom engineer and testing all the phone's functions is a huge task that I can see that with Apple's secrecy, it will make it very hard for them to test out everything with their new noise cancelling system and on a brand new phone. You have to plot out every scenario that the user MAY use the phone and accomodate them. Had Apple stuck with Audience system and just add the third microphone's function, it may turn out better.

Most users are not bothered by this issue because many of them are using the phone in a "correct" way that works out fine with the noise cancelling system on iPhone 5 - close to the face, no speaker phone, no earphone and not moving around too much. Many users are not sensitive to the "vertigo" effect due to "noise cancelling" sound waves and they see no problem. Many users do not talk long enough to feel the problem - they mainly use it as a mini computer.

I'm sure Apple will fix it in the next iOS release, but I can see it may introduce more bugs - you simply can't test for everything.

ssspluto, thanks for the information about noice cancelling. I can reproduce the problem I wrote about (see my earlier post to distinguish from other issues mentioned in this thread) with a test scenario I've developed, and that works in a very quiet office environment, with the phone resting on a desk, using Apple-provided iPhone 5 earphones. Hardly an exotic situation. Although the flaw may be in the noice cancelling system, I don't think it can be attributed to user error or an exotic use scenario.

Here's my guess - there's a threshold for the distant party signal, and below that threshold they apply strong attenuation. See the graphs referenced in my prior post. That threshold is too high, so it attenuates desired signal. I also believe they may be measuring the threshold post-volume adjustment. To filter noise coming in from the distant party, any such threshold should be applied pre-volume adjustment, and should be well below the level of any intelligible speech or meaningful ambient sound. You can test this for yourself by reproducing my test scenario, then raise the volume one click at a time. If you raise the volume to the level where the loud passages are painfully loud, you may also notice that the threshold for attenuation seems to move up, so less of the signal is dropped into the attenuation.

I'm with you on trusting Apple will be able to fix it. For me, I couldn't wait. I need to make phone calls and hear every word. I returned my iPhone 5 for now, and reverted to iPhone 4. I don't want to waste the world's or Apple's resources swapping phones when that doesn't seem to help. I do plan to buy an iPhone 5 again immediately upon verifying they've solved it.

You can’t use any earphone with the iPhone 5. It simply does not work. Many headphone companies are discovering this. Apple’s iPhone 5 noise cancelling software is totally broken and they know it. The location of the microphone on the back was not well suited for noise cancelling process.

I suspect they are turning on all microphones for noise cancelling purpose even if you plug in an earphone. This is nuts. If you put your iPhone in a pocket, you’d hear all kind of junk noise. It’s insanse that they release a phone without making sure that it works, first and foremost, as a phone!

I even suspect that using the speaker phone will not work well in many instances, especially in a noisy environment.

If Apple discovers that the location of the back-side microphone or the one in the earpiece are not really well suited for their noise cancelling software, then that means a massive iPhone 5 recall? It’s hard to believe that!

Yes, this is my impression too.

Since the effect is much more severe in my very quiet home setting, I'm going to turn on a fan or other background noise source to see if that helps. I'm also going to experiment with removing the case, and lying the phone flat so the noise cancelling microphone on the back side of the phone is flat against a sound absorbent surface. Then I'll turn it over.

http://tech.kateva.org/2012/12/voice-call-audio-clipping-and-dropouts.html