Connecting a Laptop via HDMI (Video & Audio)

This guide helps you correctly connect a Windows or Mac laptop to a display (projector, TV, or media system) via HDMI – including both video and audio.

1. Connect the HDMI Cable Properly

• Plug the HDMI cable into your laptop's HDMI output.

• Connect the other end to the projector, display, or media system (if not already connected).

• If your device doesn’t have an HDMI port, use a suitable adapter, such as:

  • USB-C to HDMI, Mini DisplayPort to HDMI, etc.

• Make sure the display or system is powered on and set to the correct input source (how to do this may vary depending on the room setup).

2. Enable Video Output

Windows

1. Press the keyboard shortcut Windows + P.

2. Choose one of the following options:

   • Duplicate – same content on laptop and external display.

   • Extend – extra screen area (e.g. presentation on external screen, notes on laptop).

   • Second screen only – only the external display is active.

⚠️ No image?

• Make sure the projector or screen is turned on.

• Check if the correct input channel is selected (e.g. HDMI 1).

• Reconnect the cable or restart the laptop if needed.

macOS

1. Go to System Settings → Displays.

2. Open the "Arrangement" tab (only visible when a second screen is detected).

Switch between Extended and Mirrored Display:

• Extended display (default):
  Two screens appear side by side; windows can be moved between them.

• Mirrored display:
  Enable the checkbox “Mirror Displays” in the "Arrangement" tab to show the same content on both.

⚠️ No image?

• Reconnect the HDMI cable.

• Check if your adapter is working correctly.

• Restart the Mac if necessary.

3. Enable Audio via HDMI

HDMI also carries audio, but some laptops may continue to play sound through their internal speakers by default. This is usually too quiet — so make sure the correct audio output device is selected.

Windows

1. Right-click the speaker icon in the bottom right corner → Open Sound Settings.

2. Under “Choose your output device”, select the HDMI device
   (e.g. “Crestron HDMI”, “Samsung TV”).

3. Test the playback using YouTube or a media player.

macOS

1. Go to System Settings → Sound → Output.

2. Select the HDMI device (e.g. “HDMI”, “Display Audio”, or the name of the projector).

3. Test the audio playback.

⚠️ Note: Some adapters (e.g. VGA or older USB-C docks) do not support audio.
In that case, use a separate audio cable (e.g. 3.5mm jack) or switch to a different adapter.

4. Troubleshooting: Is the Cable or Adapter the Problem?

If no video or audio is transmitted, follow these steps to determine whether the HDMI cable or adapter is faulty:

Step 1: Does the projector or display work in general?

• Test the same HDMI cable with another device (e.g. a second laptop).

  • If image and sound work, the issue is likely with your laptop or adapter.

  • If there’s still no signal, the cable or display input may be faulty.

Step 2: Does your laptop work on a different display?

• Connect your laptop using the same HDMI cable to another display.

  • If image appears → Laptop HDMI output is working.

  • If still no image → The problem is likely with the laptop or adapter.

Step 3: Swap out the cable and adapter

• Try a different HDMI cable.

• Try a different adapter (e.g. borrow a USB-C to HDMI dongle from a colleague).

Step 4: Check the connectors

• Are the ports loose or damaged?

• Make sure the HDMI cable is fully and firmly plugged in – it may require a strong push to click in securely.

• Check if the cable wiggles or slips out easily – this could indicate a loose contact.

Step 5: Check the input source

• Make sure the display is set to the correct HDMI input (e.g. HDMI1, HDMI2).

• Try switching inputs and note which one works.

5. Summary: Common Issues and Solutions