mobile

Hello guys,
I got the Teclast x80hs (Windows only version) and I'm very happy with it.
Since one week, the tablet doesn't charge when turned on. Windows doesn't recognize the pluged in cable. No sound, no changing icon. When I turn it off, it charges but doesnt show a charging battery.

I tried:
- changing cable (longer, shorter)
- changing charger (power bay, div. adaptors, direct to my mbpr)
- reset windwos (I cant fully reset it, because i can only reset windows with plugged in charger..)
- resintall drivers (I deleted all battery drivers in device manager)
- reboot several times

Does anyone have a solution for this?
Teclast support doesn't answer my email.

Thank you!
Marco