2. Try disconnecting and then reconnecting the HDMI cable.
3. If you are using Windows Media Player or Windows Media Center but get no HDMI audio even after it is selected as the default playback device, go to Control Panel>Sound>Playback tab>Audio/Playback device>HDMI>properties>Advance>Exclusive Mode and uncheck "exclusive mode".
4. Try a different HDMI cable.
5. Try a different HDMI port on the TV.
If HDMI is missing from Sound in the Control Panel and there is no audio through HDMI, download and install the latest Intel video and IDT audio drivers from Support.Dell.com to resolve the issue.
Download and Install the Latest Audio Driver
To download and install the latest audio drivers, perform the following steps:
Click here to enter the Drivers and Downloads page.
Select the operating system installed on your computer from the Operating System: dropdown box.
Select Audio from the Category: dropdown box.
Click the desired driver for your system displayed in the File Title(s) column to display the download page.
Click Download. You may receive a warning and an option to run or save the file.
When the Save As window appears, designate a folder to save the file that is being downloaded and click Save. The download progress window displays.
When the download is complete, follow the instructions provided in the Installation Instructions.
This will bring up the NVIDIA Control Panel. On the left column, you will find the panel names which contain settings for your graphics card. Select the Change Resolution panel to show the HD mode your display is set to.
Control Panel: Manage Audio Devices
Control Panel: Sound set for PC Speakers
Control Panel: HDMI Audio Output
Control Panel: HDMI Audio Test
HDMI Output Sound Volume
still cannot get the hdmi to play from computer to tv screen
Try this please, connect the HDMI cable and power on the tv and computer, make sure the tv input is set for the hdmi input that you are connected to and then on your computer Hold the windows key and press the letter P.