Hi MickArt4U, and welcome to the HP Forums! :smileyhappy:
I understand that you are having a problem with your speakers outputting when you plug your earphones in. I will try my best to help you resolve this issue. To better guide you, could you please tell me the full model number of your HP Envy and the operating system that you are running on it. Here are a couple of guides in case you need them.
How Do I Find My Model Number or Product Number?
Which Windows operating system am I running?
I am also including this document in hopes that the steps resolve your issue.
Connecting Speakers or Headphones (Windows 7)
I hope this helps, please let me know how it goes.
Thank you and have a great day!