Hi niles_magowitz,
Welcome to the HP Forums!
I would like to take a moment and thank you for using the forum, it is a great place to find answers. For you to have the best experience in the HP forum, I would like to direct your attention to the HP Forums Guide First Time Here? Learn How to Post and More.
I see that after having the notebook repaired, you are not getting any sounds from your headphones, but do have sound from the internal speakers.
Here is a document to assist you with this difficulty. Troubleshooting Audio Problems with External Speakers, Headphones, and HDMI Sound Devices. You can run The HP Support Assistant to help with updates and resolving issues.
I hope this helps.