A2DP Quality issue

I think there are few bugs to iron out with the Bluetooth software in the iPhone. My quality has been great when streaming A2DP. However, I will have ran into several bad stints where the audio cuts out while streaming and found that reseting the phone cures it. Kind of a pain, but hopefully OS 3.1 will address this issue. If you can't get a good stream to your car after reseting the iPhone, I'd make a Genius appointment and have them test the phone.

I just paired by 3GS with my JVC car system and I get occasional drops of exceedingly short duration. I also have annoying treble distortion that isn't really corrected by adjusting the iPhone's iPod EQ for treble reduction. I have a Motorola H820 BT headphone and it seems to stream from the iPhone 3GS just fine, although the speakers aren't high enough quality to catch much treble distortion.

OK, I've now zeroed in on the bluetooth distortion and dropout issue between my iPhone 3GS and my JVC car stereo when using A2DP. I have an iPhone dock connector bluetooth adapter from my 1st gen iphone 2G and I plugged that into my 3GS and paired with the JVC car head unit. The sound was treble distortion free and not a single dropout in 30 minutes of use. To make it even sweeting, this little Sony bluetooth dock dongle allows me not only to pause/play the music from the JVC deck, it also allows back and forward control as well. So, here's to hoping the iPhone 3.01 or 3.1 update will improve the poor initial attempt at native A2DP support on the iPhone.

I noticed my sound quality dropping on my Plantronics 855 during DVR TV shows. They all speak so low, it's as if I'm deaf now and need to use closed captioning when using the 855. But music hasn't fallen at all.

Using the standard earbuds, I can hear just fine. Very odd.

I get the same distorted treble. Kind of disappointing.

did you change any ipod sound settings? sound check, EQ, Volume control on mine are all set to off and i have no trouble...if its an app where the bad qualtiy lies, try switching the HIGH QUALITY SOUND is turned OFF

A wired connection will be better than wireless in any case.

All set to off. Just streaming the iPod app. I find that the quality of song file also impacts the quality.

Additionally, testing the same exact songs with my iPhone and my Sony Ericsson phone, it is clear that the iPhone's A2DP implementation is lacking.

Tbo6652 wrote:
did you change any ipod sound settings? sound check, EQ, Volume control on mine are all set to off and i have no trouble...if its an app where the bad qualtiy lies, try switching the HIGH QUALITY SOUND is turned OFF

While A2DP supports bitstreams into the 300kb range for High Quality audio, it also supports up to three different codecs. MP3, AAC and SBC.

It is my understanding that Apple has chosen SBC - which means your MP3s and AAC files which (in my case at least) have been meticulously maintained at 320kbps variable bit rates ripped from lossless FLAC files, are going to be re-encoded into a far inferior SBC codec for transmission to your A2DP receiver device (a Kenwood KDC-X993 in my case) - causing files that usually provide a highly satisfying audio experience into a unlistenable muddle of compression across the entire frequency range.

I'm not exactly dealing with audiophile quality equipment here - but as a discerning listener, the A2DP support as it performs in my vehicle is unacceptable.

I hear the distortions and bad quality by using the bluetooth connection between my iPhone 3GS and the jvc car receiver BT-KD1. Even with the new firmware. But the play and stop control are reliable now.

There is no improvement with firmware 3.1.2. Is there any statement from apple?

Apllication of Tomtom Car Kit solved the problem. I don´t know why. Perhaps the power supply by the car kit!?

you may look at this post:

http://discussions.apple.com/thread.jspa?messageID=11058160#11058160
and
http://discussions.apple.com/thread.jspa?messageID=11058158#11058158