Symptoms
- Sound plays through the TV but the screen stays black or shows a logo
- Video appears briefly then goes black
- Casting a different app shows video fine
- Screen shows 'no signal' intermittently during playback
Likely causes
- CommonHDCP copy-protection handshake failureProtected content requires a successful security handshake between devices; a cheap cable or splitter can break this.
- CommonResolution mismatch between casting device and TVCasting at a resolution the TV doesn't support cleanly can drop video while keeping audio.
- PossibleWeak Wi-Fi causing video to stall while audio continues buffering separatelyVideo and audio streams can be affected differently by a poor connection.
- PossibleOutdated casting device or TV firmwareCompatibility bugs between specific software versions can cause this exact symptom.
- Less commonHDMI cable or splitter not rated for the content's resolutionOlder cables may not support 4K or HDR bandwidth.
What to do
- Remove any HDMI splitter or switch and connect the casting device directly to the TV.
- Lower the casting resolution setting in the app if available, then test again.
- Restart both the casting device and the TV.
- Update the TV's firmware and the casting device's software.
- Test with a different, known-good HDMI cable.
- Check your Wi-Fi signal strength where the casting device sits.
- If the issue only happens with specific protected content (like certain movies), it's likely an HDCP compatibility issue with your specific TV/cable combination.
Tools and parts
HDMI cable rated for 4K/HDRSearch: “high speed HDMI 2.1 cable 4K”
When to call a pro
No professional repair typically needed; if it persists with a direct, high-quality cable, contact the device manufacturer's support.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.