It sounds like an older version of the app. I used to see all kinds of similar issues with Peacock on my Apple 4k device. NBC has put work in to make the app better over the years unlike say, Paramount+. I would check to see if you can manually update the app or try the 4k device and see if it works better. It could be the older chip and more limited memory of the HD device are hitting up against their limits too.