Samsung HDMI problems usually come from the input, cable, connected device, HDMI-CEC handshake, or a failing port. Work from the simplest physical checks toward settings and hardware.
These steps apply to Samsung Smart TVs with HDMI inputs connected to consoles, cable boxes, soundbars, receivers, Blu-ray players, and streaming devices.
Does this affect you?
Use this if a Samsung TV shows No Signal, cuts out, does not detect a device, or has one HDMI port that behaves differently from the others.
Check input, cable, and port
- Press Source on the remote and select the HDMI number where the device is connected.
- Unplug the HDMI cable from both ends.
- Reconnect it firmly.
- Try another HDMI port on the TV.
- Try another HDMI cable, especially for 4K or high-refresh devices.
- Test the connected device on another TV if possible.
If the device works on another port, the original port or its settings may be the issue. If it fails everywhere, the device or cable may be at fault.
Reset Anynet+ HDMI-CEC
- Go to Settings > General > External Device Manager > Anynet+ (HDMI-CEC).
- Turn Anynet+ off.
- Unplug the connected device from power for 30 seconds.
- Plug it back in and let it fully start.
- Turn Anynet+ back on.
- Reconnect HDMI and test again.
Anynet+ lets HDMI devices power each other and switch inputs automatically. It is useful, but a stuck CEC handshake can stop detection or cause random input switching.
Power-cycle the TV
- Turn off the TV.
- Unplug it from the wall.
- Hold the TV’s physical power button for about five seconds.
- Wait one minute.
- Plug the TV back in, select the correct HDMI input, and test again.
This clears a stuck HDMI handshake that can appear suddenly even with a device that worked yesterday.
ARC/eARC, updates, and hardware signs
Soundbars and receivers that use ARC or eARC must connect to the HDMI port labeled ARC or eARC. A normal HDMI port may pass video but not return TV audio.
Update the TV from Settings > Support > Software Update > Update Now. Samsung firmware can improve HDMI compatibility with newer consoles and 4K/120Hz devices.
If all HDMI ports fail with multiple devices and cables after a power cycle, the HDMI board may have failed, especially after a power surge. Samsung support or a technician is the next step.
Sources
- Samsung Support – TV Shows No Signal Message (2025)
- Samsung Support – Anynet+ (HDMI-CEC) settings (2025)
- Samsung Support – Update your Samsung TV’s software (2025)