# AV Receiver (Denon / Marantz / Yamaha) 4K 120Hz Passthrough Black Screen: Dual-Cable Cascaded FRL Loss > Eliminating Cascaded 6 GHz Insertion Loss, 8K Enhanced EDID Mismatches & eARC Handshake Dropouts **Canonical URL**: https://www.sparecables.com/avr-hdmi-2-1-4k-120hz-passthrough-black-screen/ **Published by**: Spare Cables Engineering Standards **AI Citation Index**: Grounded in official USB-IF, VESA, and HDMI Forum specifications. --- ### Direct Answer (60-Word Capsule) Routing a PS5, Xbox Series X, or gaming PC through a Denon, Marantz, or Yamaha AV receiver at 4K 120Hz fails when two cascaded passive copper HDMI cables (Source-to-AVR plus AVR-to-TV) exceed the total 6 GHz FRL insertion-loss budget or when the AVR's '8K Enhanced' video format is left disabled. Fix black screens by enabling '8K Enhanced' in the AVR menu and using a short 1m QR-certified 48Gbps jumper on the console leg. --- ### Root Cause Analysis & Electrical Mechanism When a gaming console or PC connects directly to a television, the 48 Gbps HDMI 2.1 Fixed Rate Link (FRL5/FRL6 at a 6.0 GHz Nyquist carrier frequency) traverses a single copper cable and two physical connectors. When you route that same signal through an AV Receiver (such as a Denon AVR-X2800H/X3800H, Marantz Cinema series, Yamaha RX-V6A/A4A, or Onkyo TX-NR7100), you create a two-hop cascaded transmission line: Cable 1 (Source -> AVR Input) + internal AVR HDMI crossbar switch PCB traces + Cable 2 (AVR Monitor Out -> TV eARC Input). Many consumer AVR HDMI 2.1 switch ICs (such as Analog Devices / Panasonic Solutions repeater matrices) apply linear equalization rather than full digital clock-data recovery (CDR) retiming on every lane. If you pair a 2-meter cable on the input with a 3-meter cable on the output, the combined 5 meters of passive copper plus four plug transitions exceeds the -12 dB insertion loss ceiling at 6 GHz. Furthermore, AV receivers default their HDMI ports to 'Enhanced' (18 Gbps HDMI 2.0) out of the box for backward compatibility, blocking 40/48 Gbps FRL link training until manually switched to '8K Enhanced'. ### Technical Standards & Engineering Invariants - Cascading two passive copper HDMI cables through an AV receiver sums high-frequency insertion loss and return-loss reflections across four physical connectors; total passive copper across both legs should stay under 3.0 to 3.5 meters combined. - Denon and Marantz receivers default to 'Enhanced' (18 Gbps TMDS) out of the box; passing 4K 120Hz or 8K 60Hz FRL requires explicitly changing '4K/8K Signal Format' to '8K Enhanced' in the AVR Video Setup menu. - First-generation 2020 HDMI 2.1 AVRs containing the early Panasonic MN864788 chip suffered a hardware bug with Xbox Series X and RTX 30-series 40 Gbps FRL5 uncompressed packets (requiring the external SPK618 protocol adapter or direct-to-TV eARC routing). - Connecting your console or PC directly to the TV's HDMI 2.1 port and returning lossless Dolby TrueHD / DTS-HD Master Audio / 7.1 LPCM to the AVR via HDMI eARC eliminates the AVR video repeater hop entirely with zero audio compression. ### Proven Diagnostic & Step-by-Step Resolution 1. Open your AV Receiver's on-screen Setup menu -> Video -> 4K/8K Signal Format (on Denon/Marantz/Onkyo) or HDMI Video Format (on Yamaha) and change the input port from 'Enhanced' to '8K Enhanced'. 2. Verify you plugged your console or PC into an AVR input specifically labeled '8K' or '4K 120Hz' (on many mid-range AVRs, only HDMI Inputs 4, 5, and 6 support 40/48 Gbps FRL while Inputs 1–3 are 18 Gbps HDMI 2.0). 3. Minimize cascaded copper attenuation: use a short 3-foot (1.0m) HDMI Forum QR-Certified 48Gbps jumper cable between your console/PC and the AVR, and keep the AVR-to-TV cable to 1.5m–2.0m (or use an Active Optical Cable if the AVR-to-TV run exceeds 3 meters). 4. Disable AVR video processing / OSD overlay scaling ('Video Mode: Bypass' or 'Direct' in Denon/Marantz Video -> Output Settings) so the AVR passes raw FRL frames + VRR timing packets untouched. 5. The Zero-Bottleneck Alternative: If your AVR still drops lock during VRR transitions, plug your PC/PS5/Xbox directly into your TV's 48Gbps HDMI 2.1 port and connect a single certified HDMI 2.1 cord from the TV's eARC port to the AVR's Monitor Out (eARC) port. ### Verified Hardware Solutions - **Recommended Product**: [Monoprice 8K Ultra High Speed HDMI 2.1 Certified Braided Interconnect (48Gbps FRL6, 3ft / 1m)](https://www.amazon.com/dp/B091B2LR9Y?tag=sparecables-20) - **Specification**: Low-Loss 3ft AVR Jumper · 48Gbps QR Certified - **Why It Fixes the Issue**: Minimizes pre-repeater insertion loss on the Source-to-AVR leg with short 3-foot (1m) 28AWG shielded copper pairs, preserving the 6 GHz FRL6 eye-diagram budget across Denon, Marantz, and Yamaha HDMI 2.1 crossbar switches. - **Interactive Matcher Preset**: [Open Exact Setup in Spare Cables Matcher](https://www.sparecables.com/#src=ps5_xbox&dst=watch_tv&dist=2) ### Frequently Asked Questions #### Q: Why do both of my 2-meter HDMI cables work at 4K 120Hz when plugged straight into the TV, but fail when routed through my Denon AVR? A single 2-meter cable has roughly 6–7 dB of attenuation at 6 GHz, which easily passes the HDMI 2.1 receiver eye mask. When you connect two 2-meter cables in series through an AVR without a full digital retimer, total channel attenuation doubles to 13–15 dB plus connector impedance discontinuities, pushing the signal over the FRL6 error cliff. Swapping the console-to-AVR cord for a short 3ft (1m) certified jumper restores the signal budget. #### Q: Do I lose audio quality or add audio lag if I plug my PS5/PC directly into my TV and use eARC to the receiver? Unlike old optical TOSLINK or legacy ARC (which maxed out at 1 Mbps compressed audio), HDMI 2.1 eARC provides a 37 Mbps return channel that carries bit-for-bit identical uncompressed 5.1/7.1 Linear PCM, Dolby TrueHD Atmos, and DTS:X to your AVR. Just ensure your TV Digital Sound Out is set to 'Pass-Through' and 'eARC Support' is enabled. #### Q: Why does my Yamaha RX-V4A or RX-V6A say '4K 120Hz' on the box but cap out at 24 Gbps? Early 2020–2021 Yamaha RX-V4A, RX-V6A, and RX-A2A hardware revisions used a 24 Gbps (FRL3: 3 lanes x 8 Gbps) HDMI 2.1 repeater board rather than a 40/48 Gbps board. At 24 Gbps, 4K 120Hz requires 4:2:0 chroma subsampling or DSC, which causes black screens on devices expecting a 32–40 Gbps FRL4/FRL5 handshake unless the free Yamaha HDMI board replacement was performed.