I still need to try the (sticky) mp3 utilities dehack on mine,
it seems you need an actions ATJ series chip for that method to work (mine has one)

as said, I'll be offline for a few days,
but there's a few things to try when I'm back..

This method worked perfectly for me. I thought my MP4 player was irreversibly dead, but now it is working again. I was not able to follow the instruction exactly as described ( after creating the first partition 0 I had to press start again and restart the process to create partition 1), but it worked fine. My "16GB" MP4 player from urquiquiexpress (Ebay) is now a working 2 GB player! Thanks, frozensoda!

Help, guys!
I accidentally set the size of the partition lower than the actual capacity of the flash chip (I know that because I have opened the case to check the series of the chip and h2testw says the lowered capacity is working fine). Now how do I set the size to it true capacity (or even larger, so I can use CheckFlsh again)? format in Win, HP format tool, mp3 player disk manager or even CheckFlsh cannot revert what CheckFlsh has done.

Thanks,

always determine your real memory size with h2testw before anything else..

have you tried deleting the partition you created with chkflsh?

I deleted the partition with Paragon Partition Manager. But it's still the same size.
I think the size is written in the controller chip, so if there's a program that let us change that info in the controller chip...

The program that will allow you to change the info on the controller chip is the same program that they use to hack it in the first place. I know nothing of how this is done or what they use to do it.

check this out:
http://mympx.org/forum/support-how/4...how-i-did.html

I just fixed my player with this:!!
first ran mydisktest, then isolated all bad blocks, then ran chkflsh to make the remaining memory active

It's still the same:( (lower than the chip's true capacity).
The author of ChkFlsh said "Low level init" is just a partition manager. So it's probably changing only the partition table. Is there any program that let us manually set the size of the partition (bypass what the chip controller says)?

what was the reported size by h2testw? this is always the correct capacity, or what you have left to work with
regardless of what your controller says or whatever is printed on the chip..

I think you have a bad chip, that was meant to be a certain size, but got discarded in the manufacturing proces
some hackers buy these rejects and put them in their units

on a side note, with chipgenius you can read your VID & PID codes: the PID code is your flash chip controller information
About VID PID Repairing Counterfeit Flash Drives – Steps To Succeed FakeFlashNews

I guess you're right.
Before fixing it, h2testw reported 3.5GB is OK.
The NAND chip is MT29F32G08CBAAAWC, which should have 3.7GB.
So I guess I just accidentally set the size to the correct usable memory (I set 3475MB).
At least that's comforting that I'm not "wasting" much memory.

Thanks,