Press and hold the Power button on the TV panel (not the remote).

Often lists Akai/Nordmende software for download.

Known to host LDD.M538.A138-3840x2160 files for various panel types (e.g., HV430QUB).

If the file is split into parts (e.g., part01.rar , part02.rar ), you must download all parts into the same folder before extracting. Use a tool like WinRAR or 7-Zip to extract part01.rar , which will automatically combine the others into a single .bin firmware file. 2. Prepare the USB Drive Use a high-quality USB 2.0 drive formatted to FAT32 .