After the market introduction of HDMI 2.1 had dragged on for years, Denon, Marantz and Yamaha presented the first audio / video receivers with the new version of the Audio in the past few months – / video interface – just in time for the launch of the next-generation Xbox Series consoles from Microsoft and Sony’s PlayStation 5 (PS5) as well as Nvidia’s RTX graphics cards – 30-Series. The new devices transmit videos in 4K resolution via HDMI 2.1 with 120 frames per second (short 4K 120) or even in 8K with up to 60 Hertz (8K 60) with full color resolution and increased contrast range (HDR).

As c’t in the current edition c’t 23 / 2020 reports, there is a suspected breakdown of the chip manufacturer Panasonic Solutions (now taken over by Nuvoton Technology), however, that, according to the current state of knowledge, all HDMI 2.1-compatible receivers from Denon, Marantz and Yamaha are not able to transfer videos in these ultra-high resolutions to the TV without errors with certain players. The TV screen then remains black due to the HDMI 2.1 glitch.

According to research by c’t, this problem also affects receiver models that are currently still in development – including the avantage models from Yamaha, which have been expected for a long time should. Onkyo / Pioneer and Sony are also said to have bought the aforementioned HDMI chips from Panasonic Solutions; these companies have not yet announced any AV receivers with HDMI 2.1.

Error pattern C’t encountered the problem during a test of a pre-series model of the Xbox Series X. The car racing game “Dirt 5” ran in the c’t laboratory on the TV LG CX9 with a direct connection in 4K 120 with HDR, when detouring via Denon’s HDMI-2.1 compatible AV receiver AVR-X 2700 H however, this ultra-high resolution with increased contrast range did not pass from the console to the TV as advertised. The transfer of video images from the preview model of the Xbox Series X to the television was only possible without problems in resolutions that do not require HDMI 2.1.

According to Microsoft, the pre-production model of the Xbox Series X is already based on the final hardware. However, c’t will test the retail version again with regard to the problem.

Similar problems occurred with a card of the type Nvidia RTX – 3080 – here, too, a TV set connected via the AV receiver did not deliver a 4K image with 120 Hertz and HDR. With the PS5, the transmission should work according to c’t information; c’t has not been able to verify this so far.

Since Yamaha uses the same chipset for its devices, its devices should also to be affected. The company had advertised in a press release that both next-generation consoles could be connected to the new AV receivers at the same time thanks to multiple HDMI 2.1 inputs. The new receivers from Denon and Marantz only have one HDMI 2.1 input.

Search for clues c’t received from several industries –