It sounds like the CVBS interface on your Neo V1.4 might be disabled by default. A few things you could check:
Make sure the correct firmware or device tree is loaded that enables the CVBS output. Some boards require a specific configuration to activate video outputs.
Verify that the CVBS function is enabled in your system settings (e.g., in u-boot or through a specific kernel parameter).
Double-check the board's documentation or forums to see if any jumpers or additional settings need to be adjusted.