Knowledge Base

Problem

When attempting to record or display a Mac laptop screen through MediaRecorder (or a connected AV system), the feed appears briefly and then turns red or black due to HDCP content protection on the Mac's HDMI output.

Details

Apple enforces HDCP on HDMI outputs, which prevents capture cards and recording systems from capturing the signal. The screen may register for a few seconds before being blocked. This affects MacBook and Mac desktop HDMI outputs when connected to any capture or display system that does not support HDCP passthrough.

Solution

1. Confirm that the issue is HDCP-related: the feed appears briefly then drops to a red or black screen.
2. Purchase a hardware HDMI splitter or HDCP stripping device. These devices sit between the Mac's HDMI output and the capture/recording input and remove the HDCP handshake.
3. Connect the Mac's HDMI output → HDCP stripper/splitter → capture card or MediaRecorder input.
4. The capture device will now receive an unprotected signal and the screen feed should display and record normally.
5. Note: Verify local legal and institutional policies regarding HDCP stripping before proceeding.