Denon and Marantz AVRs made after May 2021 are HDMI 2.1 bug free

Purchasers of Denon and Marantz AV receivers manufactured after May 2021 are promised an HDMI 2.1 bug free experience straight out of the box.

Update 17-Aug-2021: A few small errors in the news piece have been corrected:
1/ The serial number that signifies models which are clear of the HDMI 2.1 bug is from *******70001 onwards.
2/ Model numbers clarified.
3/ Sound United was misnamed Sound Control.

Update 19-Aug-2021: Sound United has issued a statement after concerns were raised regarding a change in DAC in its latest Denon and Marantz products. Please see the full statement at the end of this news story.

When it became apparent in late 2020 that the initial rollout of HDMI 2.1 supporting AV devices by a number of high profile manufacturers was badly affected by a hardware bug in the associated chipset, the industry had to scramble to get workarounds and fixes in place.

Now, according to a recent report by Forbes, Sound United, the owner of the Denon and Marantz’ brands, has confirmed that any of the previously affected AV receivers and amplifiers built after May 2021 will leave the factory with a new HDMI 2.1 chipset for a glitch free performance. 

This means the flaw that prevented the correct pass through of 4K/120 and 8K signals to compatible TVs is no longer present in the following models: 

For those early adopters who got hold of an affected Denon or Marantz AV receiver between the launch in 2020 and before May 2021, Sound United announced a hardware fix back in April. This involves the freely available SPK618 adapter and a firmware update and the process can be initiated by filling out a form on the Denon or Marantz websites. 

So, the obvious question for consumers ready to upgrade their AV setup with the latest Denon or Marantz AVR/Amps is, how do you tell whether the black/silver box sitting on the retailer’s shelf requires the hardware adaptor or is already bug free? Well, Forbes reports that Sound United has confirmed that models with the serial number *******70001 onwards are from the latest production runs (i.e. May 2021 onwards) and will therefore already be HDMI 2.1 bug free.

That number to look for again:  *******70001 onwards.

Of course, if you’re buying online, checking the serial number might not be that straightforward and this is another great example of why having AV hardware on sale in bricks and mortar stores, run by friendly and knowledgeable staff is so important.

Update 19-Aug-2021: Following concerns raised in the comments sections regarding the change of DAC used in the Denon and Marantz AVRs / AV Amps mentioned in the HDMI 2.1, AVForums requested a statement from Sound United to clarify the situation. The company’s response is below:

“AKM and Sound United brands have a longstanding history of working together, the loss of their factory was a big blow to the audio industry. However, Denon and Marantz procurement and engineering teams are continually searching for, benchmarking and partnering to advance new technology to prepare for circumstances like this. With every new product, our leading engineering teams ensure full system integrity across thousands of individual parts to meet sound quality standards for each brand. 

It was a significant effort for Denon and Marantz’s respective engineering teams to select alternative components which met the requirements and standards for both brands. Once selected, each team redesigned peripheral circuits and software, and underwent extensive sound quality evaluation and tuning by each brands’ sound masters to ensure an analogous level of performance. We are pleased to share our teams successfully maintained the DNA and characteristics of Denon and Marantz products, meeting the high standards of each brands’ Sound Masters and delivering the sound experience our loyal customers know and love.” 

Source: Forbes
Image Source: Sound United