internal speakers not working while earphones work

Hi jobberjobber,

Welcome to Apple Support Communities.

We understand your internal Mac speakers aren't working and you were able to review If the internal speakers on your Mac aren't working. If you have already checked that the output is set to your built-in speakers, restart your Mac in safe mode. This limits login items and performs a health check on your startup disk. While in safe mode, check for this behavior then restart to your normal user.

For an a mac with Intel processor, reset the NVRAM. Reset NVRAM or PRAM on your Mac

Regards.