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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.

share|improve this question
First thoughts: Please improve spelling. I tried to fix most of it already, but for two paragraphs I had no idea what it should like ("Edit files in folder..." and the following). It's not clear to me what those mean. Would you please edit/update that part? –  Izzy Jan 4 '13 at 13:26
when you formatted the sdcard, did you format it on the device or did you format it from a pc? –  Ryan Conrad Jan 4 '13 at 14:34
i am also not quite sure what the guy meant... im quotinig someone else –  krasatos Jan 5 '13 at 14:20
My thought: It's the card and/or Samsung's firmware. I personally have a Galaxy S2 with a 32GB card (that runs CyanogenMod aftermarket firmware, i.e. Jelly Bean 4.1, for some days now CM10.1/Jelly Bean 4.2.1). Never experienced that problem here (it's only a class4 card though). Regarding the battery problem on rescanning: Well, depending on the fill level, Android has to sift through a massive amount of files/data. –  ce4 Jan 5 '13 at 14:35

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