Make the handshake repeatable.
Start by isolating the variable.
Copy the projector or downstream sink EDID, select a known predefined EDID, or copy and modify selected capabilities. Then change one variable at a time while observing the DR HDMI 8K RX/TX information.
What DR HDMI 8K can — and cannot — tell you
Format changes can legitimately trigger HDMI resynchronization. DR HDMI 8K is most useful when you need to test whether a specific advertised capability set changes the behaviour.
Important: A stable known EDID does not replace a bandwidth-capable cable or fix a failing HDMI input/output.
A practical test order
- Confirm the source, display/AVR and cable support the target format.
- Start with a known working lower-bandwidth mode.
- Read or copy the downstream EDID.
- Present a known predefined or deliberately modified EDID to the source.
- Change one capability at a time and observe the result.
This approach is more useful than changing the source, cable, AVR settings and EDID simultaneously because it keeps the test repeatable.