Denon Marantz 3-in, 1-out 8k HDMI Switcher | AV Gadgets
Denon SPK618 HDMI Adapter for Receivers | General Electronics | Markham / York Region | Kijiji
Received SPK618 Adaptor from Denon for HDMI 2.1 fix. Sharing pics if you wondering how much extra space it would take with your current setup : r/hometheater
Denon & Marantz Solve HDMI 2.1 Bug With SPK618
Denon SPK618 Adapter - Black for sale online | eBay