Greetings and Firmware Extraxtion Error!

[soujiro_t]

Hello, this is really a good page, hello to everyone.
Since last year I have a S1Mp3 MP4 player, now I want to extraxt the firmware from it, to modify it, but I cant.
I've been reading posts, but still don't know how to extract it with the S1fwx tool.
My player can reproduce videos in format .AMV
And my firmware version is :
7513_SDK
2007/01/12
9.1.51
2006/01/19

When I run S1fwk an error appears:
...firmware version = 9.1.51
read boot record...
detect firmware size...
error: The system cannot read from the specified device.
warning: unknown firmware file
read flash...
error: The system cannot read from the specified device.
write to file 'dump.bin'...

How can I download it???
Thanks, regards.


Edited: Added this new info:
The MP3 Player Firmware Upgrade Tool says:
Device Firmware Information:
Device Name: S1 Mp3 Player
Productor: Wilson Co. Ltd.
Version: 9.1.51