Hey, give this a try.
I just switched back from Apple iPhone to the Samsung Galaxy s9+ only to be met by this music pausing problem. It's frustrating. I've tried almost everything. I'm considering returning it and switching back to an iPhone. I prefer Android over Apple, but this is ridiculous.
Baseband Version: G965USQU3BRJ5
Please fix it.
If none of the above troubleshooting steps have fixed the issue, the next recommended action is service repair. Can you send me a private message here with your IMEI number?