Disturbing noise during calls - bluetooth

[henrikgeorgson]

Hi!

I recently bought a Z4 3.0si -06. It's fitted with bluetooth and thanks to this great forum I've been able to solve the "no sound" problem since the previous owner fitted an aux in cable without reconnecting the bluetooth cables. However, when I'm making a call it sounds like crap, there's some really strange electrical noise which makes it impossible to hear the person i'm trying to have a conversation with. I've been googling and searching this forum for a solution but I've haven't found one.

I did record a call to my voicemail, it sounds like this:
https://www.dropbox.com/s/o4wgp72fnabk6wn/bt2.mp3

I've tried with two different iPhones (iPhone 5 and iPhone 4S) and I've also tried removing all paired phones from the car and pair again.

Everything sounds normal, aux (except the lack of bass), radio and sat nav voice. The persons i've been calling can hear me and the address book syncs just fine.

Any ideas?

[JFletcher]

I have pretty much the same problem with the person receiving the call from the car not being able to hear me.
The static/interference noise only is apparent when the vehicle is running, turn the vehicle off and the noise goes away.
NOTE: I can't hear any noise only the receiver.

Thinking it may be interference from the engine or possibly the lights but haven tried eliminating anything yet.

Wish there was an answer to it!!

Anybody have any bright ideas????

[srhutch]

Disconnect the aux from the head unit and see if that helps. I remember some cheap aux interfaces giving interference. Can't remember if it affected BT though.

[Chris_D]

Sounds like a ground loop issue.
Good luck with finding that!