Trouble getting started (internal problem)

I am having a few issues getting started with my new MPC 500 i purchased refurbished. As of now the MPC seems to be in factory default settings, and after trying to load samples from my computer to the MPC (via a card reader, because for some reason my computer (mac osx) will not read the MPC when directly plugged in) it will either tell me that I am trying to load an unrecognized file type (when I am sure it is a .wav) or it will seem to stall on the 'Loading...' screen.

So I tried to upgrade its firmware from 1.11 to the current 1.13, and after putting the .bin firmware upgrade file into the root file of the MPC's card, and after inserting the card into the MPC and powering it on while holding shift, the MPC will say:

OS Update mode
Total : 16 MBytes

then do nothing more.

any ideas?

the current version is 1.31, not 1.13

http://www.akaipro.com/mpc500/?tt=5
have you been there?
there's a .txt file on how to install the fw.
i haven't had to do it myself, but it says you have to push the REC button to confirm the install.

hope that helped

Yes 1.31 is what I meant, and I have read the .txt posted on the website. The problem is, is that instead of the MPC saying:

New OS 1.31
OK(Rec) or STOP

my MPC will say:

OS Update mode
Total : 16 MBytes