Hey there jedrogers,
We understand your music does not sound as expected after pausing a song then playing it again within the Music app. We'll be happy to help.
To begin, we'd recommend double-checking the steps you're using to adjust the equalizer. Check those out here: Adjust the sound quality in Music on Mac
If it's still happening, let's start your Mac in safe mode, test the issue, then reboot and test again. Use these steps: How to use safe mode on your Mac
The last step would be to create a test user account and see if the issue happens there. Create the user with these steps: Set up users, guests, and groups on Mac
And if you still experience issues, reach out to Apple Support directly and they can assist further. Contact them here: Get Support
We hope this helps. Cheers!