I fully understand you .... some people are lucky with those devices, some are not ....
Well, since your device is already at ADFU, shorting it will be useless...
The thing that you need to do now is to use ANY random firmware, as said on the dead recovery guide :
If you are on ADFU recovery mode, and the firmware for your board haven't worked, one thing you might do is to flash another (random) firmware, until you get a working usb flash disk. Then, flash your player in the normal way (without doing any short-circuit.)
Don't be that stressed, your player is recoverable!
I guess you should have bought players with defective batteries ... I would send it back for a replacement. or send it to an electric technician to change the battery.
1GB Standard s1 mp3 player. (MP-482C MAIN V8)
1GB "mp4" s1mp3 player. Not remarked.
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