BeagleBone won't start up

Hello,

I have a BBB from element14 here and it won’t start up.
Step by step.I connect either the USB or the 5V power adapter to it and the power led omes up, then i wait a few seconds and USR0-3 come up after each other. All LED’s flash once and USR 1 and 3 flash and then USR 0 gives one heartbeat and shuts down as USR 2 for the CPU comes on and stays on.

This happens with or without the sdCard inserted.
The boot button doesn’t seem to respond because when i press it and insert a sdCard nothing happens, the process repeats itself if power is applied with the button pressed.
Already tried to reconfigure the sdCard and now it should run the latest image of the Debian for ARM Linux.
I shut it down last night and powered it off and it ran quite smoothly, but when I hit the Power button this morning this happened.
I recently attempted to flash th eMMC, but unsuccessfully I might add.

Any help would be appreciated.

Best, Felix