Denon AVR-591 Firmware Update Patched: What You Need to Know
Conclusion
If your unit shows 00.70.19, you have the final patched firmware. Denon never released a newer official version for the AVR-591 after 2015. denon avr591 firmware update patched
Patch if:
are not officially published, similar models from that era received minor stability improvements for HDMI handshaking and minor bug fixes Patched Firmware Misconceptions Denon AVR-591 Firmware Update Patched: What You Need
How to apply the patched firmware update
However, over the years, two main issues have driven users to search for "patched" or updated versions: HDMI Handshake Issues over the years
Firmware updates for legacy receivers like the AVR-591 are typically designed to:
Press and hold the STATUS and RETURN buttons simultaneously. While holding them, press the POWER button.