Ensure your TV panel matches the 1366x768 resolution. Installing 1080p firmware on a 768p panel can cause a black screen or distorted image.
Do you have the of your Blaupunkt TV to confirm if this is the correct firmware version? DP.6A358.813 Firmware Free Download - Kazmi Elecom
Since this is an EMMC file, you may need a hardware programmer like the RT809H or RT809F to flash the chip directly via the ISP interface or by removing the chip.
Installing the wrong board software can permanently "brick" the TV.