Dead sansa fuze+, only ROM recovery mode

Hi,

i have a sansa fuze plus and tried to install rockbox. Unfortunately during the installation via rockbox utility I had a sd card in the PC cardreader and all files was written on that card not to the sansa player. Now the fuze plus is dead and I cannot even put it in recovery mode using: * Push the volume up button * While holding the volume up button down, plug in the USB cable * 

I connect it to Windows and Linux PC without success.

Any ideas how to fix it?

Thank you