Hello everybody! I have a strange problem with my Samsung Galaxy S2. I spent many hours by googling on the internet but haven't found anything useful so I'm trying my luck at this forum. I have a Parrot 3100 car kit and I connect my S2 to it via bluetooth. The current status is that the phone connects without problems, pairing is ok, contacts are synchronizing. If I make a call the radio gets muted and I can hear the called partner from my car speakers. So far everything is fine. But the problem is that the partner doesn't hear me. If I switch the voice to internal phone speaker, it works, but it's hard to listen the other party in the car noise. When I switch back to the car kit, the voice goes in one direction only. Actually, when I started to use the phone, everything worked excellent and I was able to make calls without problem. But then I got a notification that a firmware update is available so I installed it (I upgraded from Android 2.3.3 to 2.3.4). Since that time the calling partners don't hear me. I tried another phone and it worked so the car kit and wiring is ok. The problem is in my S2. I decided to downgrade back to 2.3.3, which is not so easy task but I managed it yesterday evening with guidance found on the internet (unfortunatelly I had to do work a factory reset to bring it back to life). After the downgrade I tried to make couple of calls from my car this evening. The first call was ok, the voice was transmitted in both directions. Wow, so I made another call to my mom. Several minutes was fine and then, suddenly, she started to repeat if I can hear her. I could but she didn't hear me even I was screaming. I restarted the phone but with no luck. I tried to make couple of more calls with the same result. I have no idea, if it's a ganeral Android problem, problem of car kit compatibility, or anything else. The forums are full of posts about problems with bluetooth on S2 but I haven't found this specific problem. Does anybody here have a clue what could be wrong? Thanks a lot in advance for any help! Reards Martin T.