I made an original port here on apple discussions on Nov, 2008. The post can be found archived here. It had to do with the fact that the person I was talking to was NOT hearing me properly. Nothing to do with range, disconnection or other issues.
3 iPhones and around 5 bluetooth headsets later, I have not managed to find a compilation that works as expected. Even now, whenever the person on the other side of the line is in a noisy environment, they cannot hear me well, so I am forced to switch to the phone, in order to have a proper conversation.
What makes this more frustrating is the fact that after an iPhone restart / BT headset repair / network settings reset, the problem goes away for a while and comes back a few days later. Or not; it's hit or miss actually.
This whole mess started for me after upgrading to iPhone OS 2.1! And it was on my first iPhone, an iPhone 3G. I really believe that all iPhone users are facing this issue, it's just that they believe it is normal to have people say to them that they cannot hear them properly under certain conditions; or they keep restarting their iPhones.
I still believe the best way to face it is to let Apple emploees in Apple stores (and specifically the Genius Bar guys and girls) know of the issue. Apple is NOT monitoring these forums, except from basic moderation. You can also send a bug report:
Send feedback to Apple through iPhone's beedback page. If you have access to the ADC program, I guess you would have access in the bug report portal.
You can use "Bluetooth quality issue: Headset mic muting bug" as a Subject and portions (or all) of the following text:
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Dear Apple,
A growing number of people have been facing issues with iPhone's bluetooth quality when making calls, for over three years now. Seems like iPhone fails to work in full-duplex mode when talking through a bluetooth headset.
You could easily replicate the bug by calling yourself on a land line and talking loudly and longly at the same time on both devices. You'll notice that -on most cases- you cannot hear yourself through the land line, meaning that the headset's mic is being muted while there is output through the headset's speaker. Talking through the iPhone itself cancels the effect. This issue does not occur when using any other phone/headset combination apart from the iPhone.
As of note, this effect is getting worse by the usage time of the bluetooth headset, meaning that when firstly paired it will most probably be unnoticed. Thus, try keeping a headset paired with an iPhone for a couple of days while using it regularly for calls and then try the above test.
As a matter of fact, there's a now-archived thread in Apple Discussions regarding the issue, dating back to 26-Nov-2008, here: https://discussions.apple.com/thread/1804116
Here is another, more recent thread in Apple Discussions focused mainly on iPhone 4, however I believe the cause of both the problems is poor echo cancellation software: https://discussions.apple.com/thread/2481487
And a more mixed-subject one: https://discussions.apple.com/thread/2498329
Please take some time to take a look into the matter. Thank you.
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