Because Onkyo has restructured its web domains over the years, the receiver’s built-in "Update via NET" feature may fail or appear grayed out due to outdated server paths. for safety and reliability. Method 1: Update via USB (Recommended)
Here is everything you need to know about that specific update, what it fixed, and how to install it. txnr646 firmware update 2021
This final update addressed two specific issues: Because Onkyo has restructured its web domains over
Optimizing Your AV Receiver: The Essential Guide to the TX-NR646 2021 Firmware Update what it fixed
According to Onkyo’s official release notes (archived from their Japanese and US support pages), the February 2021 update addressed the following: