Denon and Marantz receivers built since May are free of the HDMI 2.1 bug

Denon and Marantz receivers built since May are free of the HDMI 2.1 bug
(Image credit: Future)

Earlier this year we reported how a major HDMI error had blighted Denon and Marantz's 2020 AV receivers. Well, good news: Sound United, the company that owns both brands, has finally beaten the bug.

According to Forbes, all Denon and Marantz flagship receivers manufactured after May 2021 are officially glitch-free. This is because the latest units are fitted with a new HDMI 2.1 chip that don’t suffer the same flaws.

The bug was originally caused by a faulty HDMI 2.1 chip that prevented some AVRs supporting 4K gaming at 120Hz via the Xbox Series X.

But how do you ensure you get one of the newer, glitch-free home cinema amplifiers? Denon has tweaked the serial number of the new models: numbers that end with serial numbers from 70001 onwards should be bug-free, as they will have been manufactured after May 2021 and boast the upgraded HDMI 2.1 chip.

Of course, that's no use if you've already splashed out a not inconsiderable sum on an AVC-X6700H, AVC-X4700H, AVC-X3700H, AVR-X2700H, AVR-S960H, AVR-A110, or Marantz AV7706, SR8015, SR7015, SR6015, SR5015 or NR1711. (And in Europe, the Denon AVC-A110, Denon AVC-X6700H, Denon AVC-X3700H, Denon AVR-X2700H DAB and Marantz SR5015 DAB)

If that's you, you'll need to get hold of Sound United's external HDMI adaptor, which contains the new chip and corrects the bug. Simply fill out the form on the Denon or Marantz website to get one for free. 

Sound United says it has been "working tirelessly" to address this long-running HDMI issue. Fingers crossed Denon and Marantz receivers play nice with any device you care to connect from now on.

MORE:

Our pick of the best home cinema amplifiers

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Where to find today's best Xbox Series X deals

Tom is a journalist, copywriter and content designer based in the UK. He has written articles for T3, ShortList, The Sun, The Mail on Sunday, The Daily Telegraph, Elle Deco, The Sunday Times, Men's Health, Mr Porter, Oracle and many more (including What Hi-Fi?). His specialities include mobile technology, electric vehicles and video streaming.

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  • bristollinnet
    a dongle...a fucking dongle?

    UK owners should contact 'Sound United' for a replacement under warranty. If they refuse...go spread the word on social media.
    Reply
  • -pekr-
    bristollinnet said:
    a dongle...a ******* dongle?

    UK owners should contact 'Sound United' for a replacement under warranty. If they refuse...go spread the word on social media.

    This bug in a chipset affected more producers, including Yamaha, IIRc. There is nothing wrong with a dongle sent free of charge to the customers. It can't be fixed by the simple firmware update. What would you expect? A recall of all of the receivers sold around the world?
    Reply
  • -pekr-
    Article mentions the number 7 on a fifth position in a serial number. Not sure it is related to the bug being fixed. What it relates to, though, is the change of the DACs, from AKM to some PCM ones, due to AKM factory being destroyed by fire. Some users worry about the sound signature, while Denon tries to assure us, that they have tweaked the sound to their standards. We will have to see, what further testing reveals.
    Reply
  • Emptrix
    I wish it came with more HDMI 2.1 ports though. Having only 1 port while paying thousands is disappointing.
    Reply