SD card unexpectedly removed I have a galaxy S3 with a 32gb class10 sd card.

Unfortunately I experience the SD card unexpectedly removed - Preparing SD card phenomenon all the time. The card works ok as long as it is being used: I watch videos, mp3 etc, even on pc.

I tried formatting a couple of times and I also checked on other S3 phone which presented the same problem. I checked a 16 GB class 10 card on my phone which worked ok!

I read somewhere that this is a JB problem and that I should wait for 4.2 (I'm on 4.1.1 now)

Another solution explained that I should root my phone and do this:  


  Edit files in the folder /sys/devices/virtual/bd i/179:
  0/read_ahead_kb by pressing and holding the read_ahead_kb then choose
  open in text editor.
  
  Note: Other phones don't have 179:0.. but is ok 179:8   Replace the
  numbers in it from the default (128KB) to 1024 / 2048 / 4096
  (according to taste max = 4096) and then save and exit.


What are your thoughts? is it JB or the Card?

I should also mention that the removing/rescanning my card is killing my battery very fast.
Sounds like an SD card problem to me. I've experienced similar problems a few times over the course of the years -- a card that has worked ok for some time has started to get "ejected" by itself. Changing the SD card has always solved the problem. .. Hmm. Except once but that phone turned out to be a very problematic case in a number of ways. 

So, try out changing the SD card, I would suggest.