Hello ny5021,
Welcome to the HP Forums! I hope you enjoy your experience!
I understand there is no sound produced through your HDMI connection. I will do my best to assist you! To troubleshoot the issue, I would recommend trying the steps in this HP document: Resolving HDMI Display and Sound Issues
Please note that the document is intended for Windows 7 and Vista. However, this troubleshooting is applicable to other versions of Windows.
This document contains useful steps such as adjusting the connection settings, checking the cable and more. There are also specific steps for specific issues. You can try some of this troubleshooting if you wish.
I believe these steps will resolve the issue. Either way, please provide your results. Thanks for choosing the HP Forums. Have a great day!
Mario