Yes, I absolutely understand what you’re saying. Just like yours, my TV Connector only chimes when it breaks from a computer sound source and then only after about 45 seconds. My phone however chimes from many sources and the notification interrupts the sound source on my computer for a few seconds. And that’s why I frequently turn “Do Not Disturb” ON/OFF.
I really need to take the time to go to settings > Apps & Notifications on my phone and turn some of these pesky notifications OFF permanently. They’re irritating even when I’m not using my TV Connector. I look at these apps on my phone often enough that I really don’t need to hear chiming all the time!