My player is RK2705, 32GB faked (true 4GB flash chip) capacity, 3" touch screen from EBay Hong Kong Seller.
If you have the similar player.
This might help:
PROBLEM TO REMOVE AN MP4 hacking
Note:
After reformatted by window XP, my player still show as 32GB in Check Flash, but show the true available 3.8GB in XP explorer.
This show how the new format drive looks like after formatting:
What I have after removing the hacked memory size?