Last Friday heise online reported that the computer magazine c’t in its current issue 23 / 20 uncovered a suspected breakdown of the chip manufacturer Panasonic Solutions (now taken over by Nuvoton Technology). According to the current state of knowledge, this breakdown ensures that all HDMI 2.1 compatible receivers (also called “8K models”) from Denon, Marantz and Yamaha are not able to play videos in 4K resolution with 120 images per second (4K for short 120) with increased contrast range (High Dynamic Range) from Microsoft’s upcoming Xbox Series X console to a suitable television .

The problem came up with a test of a pre-production model of the Xbox Series X in connection with Denon’s HDMI-2.1-compatible AV receiver AVR-X 2700 H and a TV LG CX9 encountered.

Meanwhile, that has got behind the brands Denon and Marantz standing US company Sound United about the problems officially opposite the online AV magazine “Audioholics”. In the statement, for which there is no official German version yet, the manufacturer confirms that some new ‘gaming source devices’ that support the output of 4K / 120 Hz, may not work fully with 8K AV receivers. The problems would be caused by an HDMI chipset incompatibility between the devices.

Sound United further confirms that when an “affected system” is connected to the 8K HDMI input (aka HDMI- 2.1 input) of the receiver “may” fail when the source delivers a 4K / 120 Hz image and the 4K signal option on the receiver is set to “8K Enhanced”

With the designation “Gaming Source Device” and “Affected System”, Sound United avoids calling the Xbox Series X by name. That should definitely be in the interest of Microsoft, whose next-generation console, according to the current state of knowledge, implemented HDMI 2.1 without errors – and which therefore certainly does not want to be blamed for a bug in the HDMI chips of the AV receiver. It should also be noted that the “8K Enhanced” format must be activated in any case in order to be able to pass through the ultra-high resolutions at all. In no case did c’t receive a picture of the source with the structure described. Finally, Sound United emphasizes in its statement that the problem only occurs on a display that supports 4K 120. That should be clear, however.

Workarounds According to their own statements, Sound United is currently investigating the problem further and “is becoming one offer a permanent solution later “. Until then, the company proposes a number of workarounds. So you can connect the player directly via HDMI to displays that offer the HDMI audio return channel ARC or eARC and direct the sound from the source via the television to the AV receiver. Another alternative would be to set the video output to 4K at 60 Hz until a permanent solution is available. This is also the basic setting of the receivers ex works.

At the end of the statement, Sound United apologizes for the inconvenience and versic