Go to Settings > About > Version to see your current firmware.
After aggregating user reports from AVForums and Sony Community, here is the tangible impact of updating from the factory firmware (3.907) to the latest official firmware (3.979):
Solves intermittent Wi-Fi drops, Bluetooth pairing failures with soundbars, and HDMI handshake bugs with external consoles. Method 1: Automatic Over-the-Air (OTA) Update Firmware Change Update on SONY KD-43X8309C
Updates often refine the X1 processor algorithms, improving color accuracy and upscaling.
While the TV can no longer check for new updates, if you have an older firmware version, you have two historical methods to perform an update. Go to Settings > About > Version to
If updating over the air, ensure your network connection is stable and won't drop mid-download. Method 1: Automatic OTA (Over-the-Air) Update
Upgrading the firmware on the SONY KD-43X8309C is essential to extend the operational lifespan of this classic 4K television. By addressing system lag, stabilizing wireless connectivity, and patching security frameworks, this update transforms a legacy Android TV platform into a stable, modern media hub. Owners should verify their current software version under the system settings menu and apply this update immediately to secure peak hardware performance. While the TV can no longer check for
The Sony KD-43X8309C features the powerful X1 Processor, but its early-generation Android TV interface requires up-to-date software to run efficiently.