I just received word from the service centre. Apparently, they did not find any faulty mechanism with the body after performing tests on the shutters etc. It was also mentioned that the latest firmware v1.05 should not have this problem, thus maybe you guys might want to double check if your camera firmware has been updated to the latest one.
On the other hand, the person told me it might be my lens that may be causing the problem so I will have to bring down my lens another day for them to carry out the diagnostic tests. Will keep this thread updated a.s.a.p
My camera was made in Japan. Also the lens. The firmware was 1.04 but I made the update and since the first day is 1.05. This is funny... if there is no faulty mechanism why does this happens? I read on a german forum that people were having the same problem with new cameras, but the a55 model and the service changed the shutter to solve the problem.
Whenever a service center suggest that you upgrade the firware it's just an admission that they don't know what the problem is (it's a bit like asking you to turn it off and on again). I'd already upgraded the firmware to 1.05 so I know that has no effect as I've had 2 cameras fail with the 1.05 firmware fail. The current camera which is in the repair centre is apparently being repaired and they've ordered a new part (don't know which part yet); but again I suspect this is like when you take a car into a repair shop and they start replacing parts without actualy knowing what's causing the fault.
Will keep eveyone informed of my progress, but I suspect camera number 3 will fail in a couple of months as well.