iPhone 4/iOS 4 bluetooth muffled on other end

"important make sure you close some of those apps at least once a day or you will have to many things going on in the background."

It should be noted that Apple handles multitasking much differently than other OSes. Those application that appear to be "running" in the background have only saved their state and are not consuming any additional resources. There are some functions on certain applications they will continue to operate such as music playing, notifications, gps tracking, etc. but for the most part, when application go into the background the save their state so when they move back to the foreground they'll pick up where they left off.

This is very different multitasking compared to other OSes where they are truly running in the background and consuming resources. For example, the game Sudoku does not continue to run in the background, it basically saves the state it was in so when you open it back up it will continue from where it left off. This ability to save the state an application is in doesn't consume CPU time when it is put in the background. Steve Jobs had it right, I believe he said; "if you have to manage background tasks then we've failed." You should leave managing background tasks to Windows CE or Android.

I have found a work around for the same issue. When I first got the iPhone 4 I did not have an issue. It then started having a problem with voice control and then with audio quality issues in both directions using my jawbone prime. I closed all of the applications that were still loaded in the background. Instantly my bluetooth started working flawlessly.

After reading through a few hundred posts, I realized that I should try doing a powering down of the iphone. I tried the bluetooth prior to and after powering down and restarting, and the reception issues I'd been having were gone. Didn't test on a phone call yet, but took care of the audio skipping and choppiness. This would also explain the fact that I noticed it more in recent weeks than the first month or so I had the iphone 4; I haven't powered it down for quite some time.

I have a Plantronic Pro which worked flawlessly with my Blackberry 8300. When using it with my Iphone 4 the I was astounded at how badly the phone handled my bluetooth connection. In a 10 minute conversation the phone dropped the connection with my bluetooth exactly 10 times. And the person at the other end could barely hear me when I did have a connection. I powered down my Iphone, powered down my Plantronic Pro and restarted them both. Same problem. I worked on this problem for 3 days with no resolution. I now use my Iphone solely as an application device and I use my Blackberry to make calls. I am so very surprised that my Iphone cannot function as a phone.

same problem as every one else. moto h17 worked flawlessly on iphone 3g. upgraded to iphone 4 and people complain intermittently about the muffled audio. from reading the threads, i've realized this likely also happens to me when the headset is not on prior (i.e. when call is initiated from iphone). i'll cconfirm tomorrow. also have tried 2 headsets (h17 - one brand new) with same exact issue. after reading threads, seems like an OS issue to me. i hope apple will recognize the problem, explore, and fix. it's really not acceptable.

I have the muffled issue with a Plantronics Voyager 510. The headset worked great with my iPhone 3G and continues to work great with my Motorola PEBL (work phone). But on my iPhone 4 people often complain that they can't hear me.

I'll call Apple tomorrow to add to their call volume on the issue.

All,

Just to let everyone know - Try restarting your phone - it appears something is interfering, whether it be an app, or a memory leak and restarting seems to clear it up - this is not a fix, but at least tells us it's software related..

If someone can determine if there is one app that is interfering, or if it just occurs as a memory leak over time, perhaps, let us know

I'm experiencing some strange behavior: for almost 2 weeks I have no more BT problems. No muffled voice, no disconnections. The only way I can replicate the bug is to switch between speaker and BT, of course.

The procedure is the following: first, switch on the BT option on the phone; second, switch on th BT headset; the BT and the phone will auto connect. All the calls (incoming or outgoing) are made thru BT.

Using the same Nokia BH 607 which initially had severe issues.

"I'm experiencing some strange behavior: for almost 2 weeks I have no more BT problems."

It's a sad commentary when someone thinks that it is a strange behavior for their iPhone to work like it should.

Yes, you're right! Never thought how strange it sounded!

My other half and I did some experiments to see if we could replicate the bluetooth problem on-demand (both clear and muffled sounds) and... it turns out we can.

Here's what we found (and how you can test your own phone).

Call a friend via your bluetooth headset. One of you should be using the iPhone with iOS 4.x paired to a bluetooth headset, and the other should preferably have something else (and to simplify things, the other person should not use a speakerphone or headset... just have them use their phone directly.) IMPORTANT: Make sure you are BOTH in quiet rooms (there must be no background noise). As long as you each take turns talking, the bluetooth sound should be crisp and clear (e.g. as clear as it was back in the days of iOS 3.1.3)

Then, deliberately start talking over each other. With both of you speaking at the same time, the sound should go muffled for the person who is NOT on the iPhone (although the person with the iPhone wont notice.) Go back to speaking one-at-a-time and, provided you're both in quiet rooms, the sound should clear up and return to crisp unmuffled audio.

We spent several minutes on the phone going back & forth and found that if we were both in quiet rooms and took turns talking the sound was consistently crisp and we couldn't reproduced the 'muffled' audio bug. But when we both talked at the same time (deliberately as part of the test), we found we always got muffled audio.

If the remote party has background noise, it'll be as if they are continuously talking since there will be non-stop audio coming from their end of the call, and this results in the iPhone having continuously muffled audio.

So it seems to us that the bug is related to noise cancellation. It's as if the iPhone treats the bluetooth headset as if it were a speakerphone and presumes that audio output from the ear speaker would be picked up by the microphone and thus attenuates the microphone gain (probably over-attenuates) in some attempt to avoid feedback.

amazing, still no resolution.

just reported it to Apple feedback. i thought there would be a solution by now. i simply don't have time to look for solutions everyday.

i have Sony Ericsson HBH-GV435 which worked perfectly with iPhone 3. now with iPhone 4, it keeps losing connection (not pairing). Apple Genius bar replaced the phone for us, and recommended that i should not restore from backup. tried it, and still have the same problem.

now, i have a jabra bt8040, and Nissan Cube 2010 bluetooth with another iPhone 4. they have been working flawlessly until i switched to iPhone 4. the sound goes muffled and cracking up to the other side.

i am assuming it is a new problem from iPhone 4 and iOS4.

it looks like the location is related, and could be related to ambient noise level and/or noise canceling feature of iPhone 4/iOS4/BT handset/hands free.

none the less, it is unacceptable that Apple is not addressing this issue.

i love the phone, and i am dealing with the antenna gate issue, but for bluetooth there is no get around!!! i miss my commute time phone calls in my car.

Message was edited by: peter young kim

Decided to finally search on Bluetooth muffled, and found this thread. My iPhone 4 and my wife's iPhone 4 both suffer from exactly the same issue. TERRIBLE, muffled sound over Bluetooth.

The problem exists with:

1.) Motorola H715
2.) Motorola H720
3.) Jabra Stone

These three worked PERFECTLY on my 3GS running 3.1.3, so there's no excuses for them not working perfectly on my iPhone 4.

Come on, Apple! You can't hold the phone, you can't use Bluetooth. So I have a choice of speakerphone or the earbuds the phone came with!

NOT impressed! 😟

Update: We have 2 Blueant Q2 headsets that have been working perfect no muffled sound 100% perfect with both our Iphone4's. We have been testing these for 12 days now. Tried my jawbone Icon Motorola h17 and my plantronics 975 headset they are all still muffled I went right back to the Blueant Q2 it works perfectly.

People have been telling me how muffled my voice is over any Bluetooth for weeks. I went through 2 sets of plantronics 925 headsets, motorla h500, BMW Bluetooth and a jvc headunit with built in Bluetooth. The problem is with in coming calls only. When I call back, the other end can hear me just fine. This is driving me nuts. I just called apple and created a trouble ticket. They want me to go into an apple store to replace the phone. I hope a new phone fixes it.