Please try the following steps to see if they help with this issue:
1) Make sure the USB cable is connected to the Elgato Gaming hardware, and your computer.
Solution: Check the connections at both ends of the USB cable, and make sure the cable is connected to your computer, and not a powered USB port on another device, or an USB power adapter.
2) Your TV may be set to the wrong input.
Solution: Check your TV to make sure that your TV is set to use the right Input.
Look at the name or number of the HDMI port that your HDMI cable is connected to, and then match that in the TV's Input interface.
3) The Elgato Game Capture HD software may have the wrong Input selected.
Solution: Press the Settings button in the Device section of Elgato Game Capture HD.
The Settings button has a hammer and wrench icon on it.
Double check that the correct Input is selected:
4) Your PS4 may have HDCP turned on.
Before you set things up, make sure to connect your PlayStation 4 directly to your TV set or display via HDMI, without using an Elgato Gaming device.
Then, visit the Settings > System section of the PlayStation 4 interface, and turn off Enable HDCP.
After that, you can use your PlayStation 4 with your Elgato Gaming device.
If you don't turn off HDCP, then the video on your TV and in the software may flash back and forth to a black screen constantly, while the audio still plays somewhat.
5) Your TV may not support the current video resolution that your console is outputting.
Solution: Check to see if your TV can support 1080p, 1080i or 720p signals.
If your TV can't support all resolutions, change the output resolution of your console to match your TV's maximum resolution.
6) The Elgato Gaming hardware may need to be reset.
Solution: Unplug the Elgato Game Capture HD hardware from the Mac or PC, and video source. Wait a minute, and then attach everything again.
7) The Elgato Game Capture HD software may need to be reset.
Solution: Quit the Elgato Game Capture HD software, and then launch it again.
8) The HDMI cable may be defective.
Solution: Test the HDMI cable with another video source (without using the Elgato Gaming hardware), to make sure that it is working properly with your TV.
If another video source also doesn't output any video to your TV, then you may need to replace that HDMI cable.
9) The HDMI cable may be uni-directional.
Solution: Elgato Game Capture HD comes with a bi-directional HDMI cable. This is a typical HDMI cable that can be connected in either direction.
Some HDMI cables, especially those that are very long, may be uni-directional. That means they can only be connected in one way only.
If you intend to use an uni-directional HDMI cable with your Elgato Gaming hardware, please make sure that it is connected properly, according to the markings on either end of the cable.
10) Make sure your computer meets the System Requirements for Elgato Game Capture HD software.
Solution: See these articles for the System Requirements.
Elgato Game Capture HD System Requirements
Elgato Game Capture HD60 System Requirements
11) The Elgato Game Capture HD software may need to be updated.
Solution: Use the Check For Updates feature in the Elgato Game Capture HD software, to download the latest version.
Or, download the latest version from this page:
12) The Elgato Game Capture HD software may need to be uninstalled and reinstalled.
Solution: If you are using Windows, use the Windows Uninstaller to remove the Elgato Game Capture HD software.
If you are using a Mac, then erase the Elgato Game Capture HD application.
Once the software is removed on your Mac or PC, then download the latest version from this page:
If none of these steps help, then please contact Elgato Technical Support for further troubleshooting.
You can visit http://help.elgato.com to report your problem. Please let us know that you tried the steps in this article.