When I make UPI payments on the app and am listening to music/podcasts at the same time, the notification spun just stops the audio.
Usually in other apps the notification sound is played and then your previous audio starts playing, but with Jupiter it’s not the case.
I tried this! Mine didn’t stop, instead, the volume was reduced when the notification popped. It lasted for 3-4 seconds and the volume went back to normal again.
Could it be device specific? 
It happens specially with Bluetooth headphones more I guess ?
I tried with my backup iPhone and it happened there as well