[Q] sd card "speed fix" not working

I am trying to follow the instructions from this thread to increase the speed of my card (I just put a brand new class 4 Kingston 32GB card):

Unfortunately since I have less than 10 posts I am not allowed to post a reply to that topic so I'm posting a question here instead. I tried this "fix" and all it does is break my ability to mount the sd card. I am running Ubuntu 10.10 on my desktop here and generally when I insert the USB cable and change to "disk drive" mode, gnome automatically adds an icon to my desktop and prompts me if I want to open the photos with f-spot or the music with rhythmbox.

So I changed back to charge only mode, fired up a terminal and dropped into an adb shell. I ran:

# su # cd /sys/devices/virtual/bdi/179:0/ # echo 128 > read_ahead_kb

Then I exited from my shell and changed the usb mode to "disk drive" but nothing happened. A few seconds later I got a notification on my phone's taskbar that there was a DRM limitation. Really? That's curious because there is no media loaded on this card yet -- I *just* formatted it. Not sure what gives.

Changing the value back to 4 didn't seem to help but power cycling the phone did. Now I can at least mount the card as a disk drive again, and it's currently copying over about 25GB of music...very, very slowly (~2.4MB/s). I guess I'm going to bed soon so it doesn't matter if it takes 2.5 hours or 10 minutes but I'm still curious why this "speed fix" isn't working for me. It seems to be working great for everybody else. At a minimum I would expect my card to write at 4MB/s since it is a class 4 card. And given Kingston's reputation and the fact that this was retail packaging I imagine it's a legit card. I paid more for the Kingston so I hope it wasn't a waste of money.

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