HDMI 2.1 Chipset Bug in AV Receivers Causing Gaming Problems



Audioholic Field Marshall
Without knowing anything about this, I really question the HDMI certification process, too, and the culpability there. Reminds me of the FAA letting aerospace manufacturers self-certify; what could possibly go wrong?
Well, the spec wasn’t final until late January. But, manufacturers were putting HDMI 2.1 “features” in their products to sweeten the pot. Ultra Certified HDMI cables just showed up though many were selling cables that were HDMI 2.1 “capable.” Yeah, it‘s all good til’ none of it works. As was stated earlier, early adopters pay the price. The folks that bought the first round of 4K TVs felt it too. I can hear the Soup Nazi, “No HDR for you!”


Audioholic Field Marshall
This is the typical first adopter problem: You get the bragging rights but the product at it's inflated price is buggy as hell.
M Code

M Code

Audioholic General
Thanks for getting back on this. I appreciate it.
Please don't misunderstand, SU deserves to wear pie on their face over this. So does Yamaha.

Out of curiosity, as an 'insider,' do you know if Nuvoton-Panasonic has updated the chipset for new products coming out this year? Or are we in for a long morass of HDMI 2.1 implementation?
There are some updated HDMI 2.1 ICs now in testing..
But don't expect to see these until 1st quarter 2022...

Just my $0.02... ;)


Still stunned by the anger directed at one company who isn’t even responsible for the flawed product in question: the actual chipset itself.
Yes, at least two major companies dropped the ball on implementation. I get it. We’ve been over this… six pages ago.
So everybody freaking out over just Sound United actually doing something to make their systems work as advertised is beyond silly.
Panasonic Solutions, now Nuvoton Technology, is the manufacturer: they released and sold buggy gear. Sony and Microsoft have a responsibility in this too, frankly. No this does not absolve SU and Yamaha for their part in not testing things… but it would have required them having PS5s and XBox with working content over a year before the consoles were publicly available.
(Perhaps @M Code could she’d light on when SU and Yam went to production vs Sony and MS going to production, please. :) )

On top of all of this, I haven’t seen one person bag on Yamaha the way everybody is piling on SU. And, SU has actually done something about it. Whether you like it or not: immaterial. But they have done something to Yamaha’s nothing.

And in the end, this is really still just a big lesson in the risks of both being First To Market, as well as Early Adoption.

*steps off soapbox
Why should I give any thought whatsoever to who SU suppliers are other than mere curiosity? I have a relationship with Denon/Sound United via my purchase with their written warranty, not Nuvoton or any other of well over a 100 companies that have parts in the product. If SU has a problem with a supplier they can deal with them legally or through negotiations, I couldn't care less. I think it is quite weird that anyone would have any anger at all with one of their suppliers. It is the responsibility of the manufacturer to make sure they have engineered a product competently and as advertised. SU chose to use the part in question and it is their responsibility to make sure it works. SU clearly failed and needs to make it right, this silly box is not making it right.
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Audioholic Field Marshall
Early adopters need a break on this one and EVERY manufacturer advertising and selling supposed HDMI 2.1 gear deserves what they get from this mess. The f#%kin’ spec was not finalized! Yamaha is supposedly putting out updates next month. If any of them address this issue is unknown. Anybody who purchased a 2020 Yamaha knew those features were not working out of the box but those units had other issues. Denon/Marantz units were supposed to have working HDMI 2.1 features. Those two flimflam men should be selling used cars on the bad side of town, not pitching quality audio gear. Folks would know exactly what they were dealing with in that venue. Yeah, I said it. I said worse to Yamaha and got a free receiver out of them. The SU units do not work as advertised. They came up with a workaround. Can we stop with the fanboy s#%t? You’d think this was an Apple forum. Once working units are produced, SU could take trade-ins and give discounts to those who purchased 2020 models and want a fully functional unit. Just an idea. Oh, Happy May Day everybody!:p


Audioholic General
I think the HDMI folks also deserve some of the blame. Having both compressed and uncompressed 4k120 allowed guaranteed that implementers would make incompatible choices.

That said, SU could have maybe picked up the phone and asked Sony and Microsoft how they were implementing 4k120 video before deciding on a chip set.


Audioholic Ninja
The first clue HDMI 2.1 was not close to ready was seeing TVs and AVRs only supporting 40g instead of 48g.

I’ll try to wait for 2023 or 2024. :)
M Code

M Code

Audioholic General
Without knowing anything about this, I really question the HDMI certification process, too, and the culpability there. Reminds me of the FAA letting aerospace manufacturers self-certify; what could possibly go wrong?
1 of the major advantages of having an HDMI product being submitted for compliance to the HDMI testing center beyond just processing and operation of supporting features ..
Is that the product is tested for interoperability with other HDMI components including CEC...
Note that certain products like a cable box or satellite tuner or game console connected directly to the HD display with HDMI has a wider tolerance for reliable operation. Because it is simply a source, sending an encoded stream to the HD display for decoding... But an AVR does much more; its HDMI circuit is actually a "repeater..."
The AVR does the following:
  • Takes the incoming encoded HDMI stream
  • Extracts the audio and decodes it for processing and sound output
  • Extracts the video, decodes the stream
  • Re-encodes the HDMI stream exporting to the HD display
  • Re-encoded HDMI stream/timing must be a mirror image of the native incoming HDMI input stream
Just my $0.02... ;)

AVR Enthu

It shoud be noted that Sound United's video demo of the new adapter box shows that the signal passed through was 32 Gbps at 8-bit, with no HDR and no VRR. The XboxX console is capable of outputting 40 Gbps, with HDR and VRR to capable TV. It works perfectly fine, at 40 Gbps+HDR+VRR with LG TVs when connected directly to it.

HDR and VRR are still officially advertised features on AVRs by Sound United. Both features have not been shown to work with a new HDMI adapter box. What is going on here?

The last section of the video demo does show info screen with 40 Gbps, but this is not signal from XboxX. This section of new video is a fake - it's a copy and paste from their December's video where they showed video connection with Nvidia's 3080 GPU, which was 40 Gbps signal. Why did they copy and paste irrelevant information into new video?

At 3:33 in the new video we see 10-bit at 40Gbps. We don't know what the source of the signal is here. New video clip is not 100% original recording.
If you freeze 3:33 moment in the new video and freeze December's video on 6:30, you will see exactly the same room and furniture setting, position of cables and devices.
New video with HDMI adapter 32 Gbps
December video with Nvidia RTX 40 Gbps

Therefore, new HDMI adapter has not been demonstrated to pass 40 Gbps with XboxX; only 32 Gbps - a degraded signal.

Someone needs to call or write an email to SU and request from them to clarify why is it that they did not show general info menu with new HDMI adapter at eh end of new video, but instead used information from old video with Nvidia GPU. Are they trying to hide that new adapter can only pass through 32 Gbps?


Junior Audioholic
All this activity over a single input is a joke. There are still at least two more devices for gamers that need consideration. That box should have had three in and one out to compensate for the lack of inputs on the receivers. The industry desperately needs a modern switcher and as of today, none exist. One with not only HDMI in but cat6 for extended runs. I would imagine a modern HDMI 2.1 switcher with five in and one out that does the signal processing to compensate for the display device would sell tremendously to not only the mature gaming market but for high end videophiles wanting future proof options on their 8K projectors and TV's to distribute high bandwidths from their server closets.

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