Direct answer
Black screens and intermittent handshakes commonly follow a mismatch in bandwidth, EDID, HDCP, refresh rate, color depth, HDR, cable performance, or power-up sequence. A new source or display may enable a format that an older matrix or extender cannot pass. Shared systems also need a strategy for displays with different capabilities.
Troubleshoot the signal path methodically: record the failing source and format, confirm firmware and certified cables, test a direct connection, inspect EDID and scaling rules, and validate every endpoint after reboot and input switching. Randomly replacing cables or forcing the entire home to the lowest format can hide the real issue. Changes should be documented so a future display or source upgrade can be evaluated before installation.
How this answer was prepared
Camelback Smart Homes publishes this FAQ library for homeowners, design professionals, builders and property teams comparing integrated technology. Answers begin with the practical conclusion, then explain the factors that can change it.
Limitations: This is general educational information, not a site-specific design, quote, code determination or compatibility guarantee. Final requirements depend on the property, construction, infrastructure, equipment versions and project goals.