I have this problem ALL the time. I know I have a very fast, and moderately unreliable connection. That is, I have great download speeds, but no matter what internet radio station I pick, 40 minutes is a long time for Roon to play continuously.
Like I said, I know for a fact that my internet just stops for a few seconds an hour, or so. That’s just normal and to be expected in this neck of the woods. I’d love it if I didn’t have to manually reset things.