: The site KenotronTV and various Telegram groups often host USB-upgradeable versions of this firmware for various brands (Skyline, Akai, Eurostar) using the same board. Installation Steps
Press and hold the on the TV panel (not the remote) and then plug in the power cord.
How to update the firmware on the SMART Board GX (V4) Plus (2026)
: Do not power off the TV during this process, as it can brick the mainboard. Technical Verification Board : TP.MT5522S.PC822 Panel : CC575PU1L (often associated with 58-inch 4K panels).
Keep holding the button until the "Software Updating" screen appears on the TV.