**Remont-aud.net: ** A massive repository for TV firmware. You will likely need to register and pass a short technical test to gain download points.
**Electronics Service: ** Look for sections dedicated to "Main Board" dumps, searching specifically for the motherboard code MT31SR MAD2HG . Critical Safety Tips
If your TV still boots or if you have an SPI programmer (like a CH341A), always dump and save your original firmware before overwriting it.