Music pause mutes the volume

[dan_l2]

Device

OnePlus 6T 

Operating System

Android 9

OxygenOS 9.0.15

2019.6 Security Update

My Question or Issue

I'm suffering from volume issues on my seat car \ Razer Bluetooth speaker.
When pausing the spotify music, it automaticlly mutes the bluetooth volume and i'm unable to listen to something else (For example: Whatsapp recording \ videos, Facebook videos)
If i'm trying to play it while Spotify is playing i'm able to hear it.
Killing Spotify also fixing the issue.
It doesn't happening on Bluetooth headsets.