Audio dropouts on Xfinity streaming app using Apple TV 4K

I get periodic 2-3 second audio dropouts when I'm using the Xfinity streaming app on Apple TV 4K with 4 different Sony smart TVs. I get no audio dropout on any other apps eg YouTube, Prime, Netflix etc and no video dropout. The dropouts can be every 10 -30 minutes; more frequent in the evening. I've had 9 Xfinity calls and one visit, and done all the troubleshooting with no improvement. I've updated Apple TV and Sony software, deleted and installed the app, rebooted the gateway, signed in and out of the app, and the tech adjusted my input level tot the gateway. Xfinity has no next step and finally told me to call Apple. Xfinity has the app for Apple TV but not on the Sony Google or Android. Any suggestions?