CEC Adapter — Not Being Detected

Modified on Thu, 30 Apr at 1:35 PM

If libcec cannot find the USB-CEC Adapter, or CEC-Tray reports no adapter is connected, work through the steps below in order.

Step 1 — Check the Physical Connections

Confirm the USB cable from the adapter is firmly connected to a USB port on your PC.
Try a different USB port — some USB hubs or extension cables can cause detection issues. Connect directly to a port on the PC itself.
Confirm the HDMI cable is firmly connected between your PC and the adapter, and between the adapter and the TV.
Ensure the TV is powered on — the adapter requires an active HDMI connection to initialise correctly.

Step 2 — Verify libcec is Installed Correctly

Open a Command Prompt and navigate to the libcec installation folder:

cd "C:\Program Files\Pulse-Eight\USB-CEC Adapter"

If this does not exist, try:

cd "C:\Program Files (x86)\Pulse-Eight\USB-CEC Adapter"

Run the following command:

cec-client -l

If libcec is installed correctly and the adapter is detected, you will see it listed here. If you see "No adapters found" or an error, continue to the next steps.

Step 3 — Check Windows Device Manager

Press Windows + X and select Device Manager.

With the adapter connected, look for it under Ports (COM & LPT). It should appear as a COM port entry. If it appears with a yellow warning triangle, there is a driver issue — see Step 4.

If the adapter does not appear at all in Device Manager, try a different USB cable or USB port. If it still does not appear, the adapter hardware itself may be faulty — contact Pulse-Eight support.

Step 4 — Reinstall libcec

If the adapter appears in Device Manager with a warning, or if cec-client reports no adapter, try a clean reinstall of libcec:

Uninstall libcec via Settings → Apps, search for "Pulse-Eight" and uninstall.

Reboot your PC.

Download and reinstall the latest version from: github.com/Pulse-Eight/libcec/releases — use libcec-x64-7.1.1.exe for 64-bit systems.

During installation, ensure all components are ticked on the Choose Components screen.

After installation, run cec-client -l again to test.

Step 5 — Update the Adapter Firmware

If the adapter is detected by Windows but not by libcec, the adapter firmware may need updating. See: Upgrading the firmware of the CEC adapter

Step 6 — Check CEC is Enabled on Your TV

The adapter requires CEC to be enabled on the connected TV to function. Check your TV's settings menu for a CEC option — the name varies by manufacturer:

Samsung — Anynet+
LG — SimpLink
Sony — Bravia Sync
Panasonic — VIERA Link

Ensure this setting is enabled. On some TVs it is disabled by default.

Step 7 — Use Monitoring Mode to Verify Detection

If the adapter is listed by cec-client -l but CEC commands are not working, use monitoring mode to verify the adapter is receiving CEC signals from the TV:

cec-client -m

Press buttons on your TV remote. If CEC messages appear in the output, the adapter is working and the issue is with command configuration rather than detection. If nothing appears, CEC may not be enabled on the TV.

See: CEC Adapter — Monitoring Mode

Still not detected? Contact Pulse-Eight support with a description of what appears in Device Manager and the output of cec-client -l.

Email: cs@pulse-eight.com | Submit a support ticket