In October 2021, Onkyo released a silent revision: v2131-8030-5080. This update only appeared for units that had already installed the February patch. Its only change was:
“Corrects an issue where the zone 2 speaker output would remain active after the main zone was powered off.”
No new security or feature updates were included.
The txnr646 firmware update 2021 (version 21110-11010-1210) represents the final and most polished software state for the Onkyo TX-NR646. While it doesn’t add headline features like HDMI 2.1, it resolves long-standing audio, video, and network issues that have frustrated owners for years.
If your receiver is still running original or pre-2021 firmware, performing this update is one of the most effective ways to extend its usable life. The process is free, takes under an hour, and dramatically improves reliability with 4K sources, gaming consoles, and streaming apps.
Bottom line: Update your TX-NR646 to the 2021 firmware today—your ears and your HDMI devices will thank you.
Have you performed the txnr646 firmware update 2021? Share your experience in the comments below, or visit the AVSForum TX-NR646 owners’ thread for advanced troubleshooting.
Last updated: 2025 – This guide remains accurate as no further firmware updates have been released for the TX-NR646 after 2021.
The "Great Update of 2021" for the Onkyo TX-NR646 wasn't just a routine patch; for home theater enthusiasts, it was a long-awaited digital revival. The story follows
, an audiophile whose trusty TX-NR646 had begun to feel like a relic of a bygone era. For months, his unit had struggled with intermittent connection drops and the occasional "handshake" issue with his newer 4K devices. He spent his evenings scouring forums like Onkyo Support Page , waiting for a sign of life from the manufacturer. txnr646 firmware update 2021
Then, in late 2021, the notification finally appeared. The firmware update promised more than just stability; it was a performance tune-up for a classic workhorse. The Digital Transformation
: Leo cleared his afternoon, knowing that a botched firmware update could turn his beloved receiver into a very expensive paperweight. He bypassed the flaky Wi-Fi and plugged in a dedicated Ethernet cable for maximum stability. The Progress Bar
: As the "Updating..." text blinked on the front panel, Leo watched with bated breath. This specific 2021 update was designed to improve Chromecast Built-in
performance and resolve minor bugs that had plagued the DTS:X and Dolby Atmos processing during high-bitrate playback. The Payoff
: Once the "Complete" message scrolled across the display, the transformation was immediate. The Spotify Connect lag vanished, and his 4K Blu-ray player finally synced with the receiver in seconds rather than minutes.
The 2021 update proved that even as newer models hit the shelves, the TX-NR646 still had plenty of heart left. For Leo, it wasn't just about the software—it was about keeping the music playing for another year. official changelog for this particular firmware version?
The most recent official firmware update released specifically for the Onkyo TX-NR646 was issued on December 1, 2020 (Firmware Version: 1110-6060-1106
). While no new updates were released in 2021 specifically for this model, many users sought this late 2020 update throughout 2021 to resolve persistent bugs. Update Highlights (Version 1110-6060-1106) Web Setup Fix
: Resolved an issue where users were unable to change customer settings within the web-based setup menu. Sirius XM Support Do not unplug: If the power fails during
: Fixed a bug that prevented song information from displaying correctly during Sirius XM radio playback. Stability & Compatibility
: Included cumulative improvements for DTS:X compatibility and general system stability. Key Considerations & Issues 4K HDR Limitations
: Some users reported that after installing recent firmware, the previous "secret" key combination (BD/DVD + Power) to enable HDMI 4K Enhanced
mode no longer worked, potentially affecting 4K HDR passthrough for certain devices. Update Failures : A common issue during the update process is the Error 0-21 , which typically indicates a network failure. strongly recommends using a USB flash drive
for a more reliable installation rather than a wireless connection. Hardware Vulnerability
: Older units may experience "DSP" update hangs (e.g., stopping at 70% or 90%), which can sometimes indicate a failing internal memory chip rather than a software bug. How to Update
For those still using the Onkyo TX-NR646
, the firmware update situation in 2021 was a bit of a mixed bag. While newer models like the TX-NR696
received significant features that year—such as Klipsch Optimized Mode and expanded SONOS device support—the largely transitioned into maintenance mode. The December 2020/2021 Baseline The most "recent" significant update for the In October 2021, Onkyo released a silent revision:
was released on December 1, 2020, and served as the baseline for 2021. This update was critical for stability, addressing:
Web Setup Fixes: Resolved issues where customer settings could not be changed via the web menu.
Sirius XM Fixes: Corrected song information display issues for Sirius XM radio.
General Stability: Ongoing minor bug fixes to prevent audio dropouts during certain content playback. Community Tips & Warnings Since the
is a 2015-era model, forum users in 2021 shared several "lessons learned" to keep these units running:
The "USB Over WiFi" Rule: Long-time owners strongly recommend avoiding network updates (WiFi/Ethernet). Many users on Reddit reported "bricks" or endless "Now Initializing" loops when updating over the air.
Manual Updates: If your receiver hasn't been updated, it's safer to download the files to a USB drive (formatted to FAT32) and update through the front panel.
Dolby Vision Limitations: Despite various updates, many users confirmed that the TX-NR646 does not support Dolby Vision passthrough for all devices (like the 2019 Shield Pro), and no 2021 firmware fixed this hardware-limited capability. Checking Your Version
To see if you are on the final stable version, navigate to:Setup → 8. Misc → Firmware Update.The latest reported version number for this model is typically around 1110-5060-1106.
Note: The TX-NR646 is a network AV receiver manufactured by Onkyo, released in 2015. By 2021, the device was six years old, and firmware updates were focused on stability, HDMI handshake fixes, and security patches rather than new features.