IPhone 5c IOS7.0.3, other people can no longer hear me during calls unless I tap into speaker mode and back?

Question

Hi,
I'm currently using an iPhone 4S, but my partner has just bought an iPhone 5c. A while ago, before the IOS7 upgrade, my phone would for some reason act as if I had clicked mute during calls. Nobody would hear me, but I could hear them perfectly. The only fixes were to hang up and recall them back, or to switch it to speaker mode and back again. Very annoying. However, after updating my IOS, it suddenly stopped doing this. It was fixed, I was happy, game on.
But recently, my partners phone which was working perfectly fine before the new IOS7.0.3 update, has developed this problem. Exact same issue, exact same solution. I wouldn't mind so much, but shes bought this phone in the last month, its a brand new phone, new software, new model... It shouldn't still be doing this! Whats worse is that when driving, its very dangerous for her to have to keep switching between speaker and not just to get her phone working. (She drivers with the phone in a cradle with hands free on).
This issue is... Annoying. I've found that its not exactly a rare thing, and that a lot of people have had it for quite a while, but the only solution I've seen is to open the back of your phone and cover a certain part with paper/cardboard... Not exactly what we want to do is it.
Does anybody have any advice or a solution to this, as I'm going a little crazy trying to reset everything and fix it!
Thanks in advance!

Answer 1

Same issues here. Sometimes during outgoing calls, people cannot hear me at all, even when the signal strength is good. Only solution is to soft reset the phone. A couple of times the person could hear me for the first few seconds of the call then it dropped completely.
I also experience the issue with the 3G data as you described (I think they are related... i.e., when the 3G data isn't working, the issues with outgoing calls exists too). The phone will just randomly seem to lose it's internet connection, even with full signal strength. Soft reset/toggling airplane mode fixes this.
I called Apple support; they asked if I was covering the microphone during outgoing calls (as if I'm that stupid). Come on Apple, I have a University degree in Computer Engineering, don't insult my intelligence! They then asked me to restore the phone (which I already did). Next solution they offered me was to replace the phone by sending me a new one first (at a cost of $35), or I could send it back and be phoneless for a week while they send a new one (which is not an option for me). I also put on a $30 Invisibile Sheild so if I exchange it, I already lose that. I believe the issue is not with the hardware, since the microphone seems to work just fine. Given that it is intermittent like this, it seems there's a software/firmware error somewhere that gets the phone into a bad state.
Very disappointed that the $800 phone I just bought functions worse for phone calls than the Nokia brick I had 8 years ago.
If anyone has a permanent solution for this that doesn't involve exchanging the phone, please let me know.