Txnr646 Firmware Update 2021 -
Cause: Corrupt download or USB drive not FAT32.
Fix: Reformat USB, re-download firmware from Onkyo, and retry.
Before updating, check your firmware version via the on-screen display: txnr646 firmware update 2021
If your version is lower than 1091-1010-0000-0010, the 2021 update applies to you. Cause: Corrupt download or USB drive not FAT32
A: You can, but you remain vulnerable to HDMI handshake issues with newer devices and network security flaws. It’s a low-risk update with high benefit. If your version is lower than 1091-1010-0000-0010 ,
Perhaps the most strategic element of the updates
By 2021, the TX-NR646 was six years old. Early firmware versions (from 2015–2018) suffered from three notorious issues:
The 2021 firmware update was specifically engineered to resolve these legacy pains. It is widely considered the "end-of-life" stable patch—meaning if your receiver is still on a 2019 or earlier build, you are missing critical stability fixes.