Problem listening through headphones on MacBook Pro 2018

Hi there - I have to uninstall and then reinstall Audacity every time I use it on my MacBook Pro. I select “external headphones” in the dropdown menu on audacity and the audio comes out of my inbuilt speakers. Its nothing to do with the Mac. The headphones work just fine with all other playback, Youtube, etc. It’s purely an issue with Audacity.

Has anyone else experienced this issue?

Lou

Are the headphones connected to the analog headphone jack, or are they USB or Bluetooth or something?