Next-generation AV receivers from Denon, Marantz, and Yamaha have a faulty HDMI 2.1 chip and the problem may not be fixable via firmware, according to a report by Heise.de.
Faulty HDMI 2.1 receivers
In recent months, Denon, Marantz, and Yamaha have announced or launched receivers with HDMI 2.1 pass-through and features. HDMI 2.1 is required if you want to pass-though PS5 or Xbox Series X's highest quality video signals (4K120 with HDR, 8K60) through a receiver.
German magazine Heise (or c't magazine) has carried out testing in combination with Xbox Series X and the Nvidia RTX-3080 graphics card. It concluded that the HDMI 2.1 chip in the receivers is faulty, resulting in a black screen when trying to process 4K120 with HDR and 8K60 signals.
All HDMI 2.1 receivers currently source the HDMI 2.1 chip from Panasonic Solutions (now owned by Nuvoton Technology). Heise ascribes it to a known bug in the chip that may not be fixable via firmware.
- "According to research by the 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. 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," said Heise.
The Marantz 2020 SR receivers are among the affected models
Denon & Marantz respond
In a statement to Forbes, Sound United (Marantz, Denon) acknowledged the issue and added that it will offer a permanent solution at a later date.
- "Some new gaming source devices that support 4K/120Hz output may not work fully with Denon (or Marantz) 8K AVRs. You may discover this incompatibility issue due to a HDMI chipset mismatch between the devices. When the affected system is connected to the AVR via 8K HDMI input and set to output at 4K/120Hz, and the AVR’s 4K Signal Format option is set to “8K Enhanced,” you may not see the system’s source video on their display, and may not hear the system’s source audio processed through the AVR. This problem is only present when a display that supports 4K/120Hz is used," Sound United said in a statement to Forbes.
Leaving the receiver out of the connection chain solved the problem. A direct HDMI 2.1 connection from Xbox or Nvidia card to an HDMI 2.1-capable TV worked as intended, said Heise. Testing with PlayStation 5 will be carried out later.
Also read: List: 4K TVs and 8K TVs with HDMI 2.1
The HDMI 2.0 system in the receivers work as intended. The reason why it affects only HDMI 2.1 is that HDMI 2.1 is based on a new signalling system called FRL (Fixed Rate Link) that enables higher bandwidth (compared to HDMI 2.0's TMDS signalling system).
Also read: HDMI ARC (Audio Return Channel) and eARC explained
If you own one of these receivers, a TV with HDMI 2.1, and are waiting for PS5 or XSX, you should, when you receive the console, connect it directly to the TV and pass audio back to the receiver via the TV's HDMI eARC connection. eARC will allow you to utilize PS5 and XSX's new video/gaming capabilities even with classic HDMI 2.0 receivers (that support eARC).
- Source: Heise, Forbes