This isn't a complain post as I'm thankful for what @comex and @saurik do for the community. I just wanted to let everyone know my experience with jailbreaking through jailbreakme.com.

My device is an iPhone 4 and was running 4.0.1 jailbroken by jailbreakme.com. I have been waiting for my Otterbox Defender to arrive so I had not activated the phone. I did however update the firmware to 4.0.1 and jailbreak the day after jailbreakme.com was live. The case came today so I activated my jailbroken iphone. As I was setting it up I received a phone call and as usual answered with my bluetooth headset. The caller was like you are garbled I cant understand you. I disconnected the bluetooth and conversed through the phone without issue.

I exclusively use bluetooth when on the phone. I tried three other bluetooth devices with the same result. I figured I had a faulty phone. I did a restore of 4.0.1 and tested the bluetooth. It is late here so I used the voice-mail on my Skype number. The first call I recorded was a non jailbroken call via Bluetooth. The audio was fine. I jailbroke via jailbreakme.com (no reboot) and called the skype voice-mail. The audio was still clear and sounded fine. I rebooted the phone and called my voicemail a third time. This time the audio was garbled and echoed. It was like too loud, clipping and there was an echo this time. I restored to 4.0.1 again and tested my audio which was crisp and clear.

I am wondering if anyone else has had this issue? At this point I will have to go without JB as Bluetooth is more of a priority (Barely!) sad but true.

As a side note Bluetooth audio worked great on my 3GS running 4.0.1 and JB at jailbreakme.com.