I just wanted to jump in here quick. I have been having this bluetooth issue since i got my 2012 Golf in April of 2012. I currently have the RCD510 head unit in the vehicle, at the beginning of owning the car i noticed if i had any music on the ipod on my iphone (4S at the time) that it would automatically pick it up via bluetooth, and play through the car. It would NOT switch to BT-Audio though, then if you looked at the iphone, music was playing in the background, causing the battery to die. Its frustrating because if you drive an hour, you arent REALLY supposed to be looking at your phone legally anyway so you wouldnt notice and you'd be down 70-80% battery all of a sudden. I thought this was a phone problem, luckily, i was an apple tech and was able to troubleshoot and get a hardware replacement. It didnt solve it. Since then i have had 3 phones, on the 5 now, and they all do the same thing. My girlfriend drives a 2011 Tiguan, same exact head unit, not the same issues. I spoke to VW 3 times asking about reloading firmware or asking for updates, they never helped. I escalated it to VW Canada and they brought it in again specifically to troubleshoot. I showed the service writer and 2 technicians at VW the issue, very easy to explain and easy for them to see, but after they did an official scan for errors, they got nothing. They ordered a new head unit anyway for me since i know the entire dealership and sort of demanded it. I had it installed yesterday, (another RCD510) and its the same thing. I am putting through more and more complaints with VW to upgrade the unit to an RNS510 and see what comes from it. Even worse, in the last 2 weeks, it connects to the phone anyway, without music on it, and tries to stream anything it can (which is nothing) but still kills the battery. In the last 9 months i have confirmed it is NOT the phone, it is the car itself. I am now at the point after i start my car i have to go into the phone menu on the MDI > Bluetooth > Media Player > Connected Devices > (My Phone) > Disconnect...all manually...EVERY SINGLE TIME I START MY CAR. Anyway, i made a discussion account solely to post in here, i am awaiting a word from VW Canada to upgrade the hardware and see if that helps. I will keep everyone posted!