I bought my wife a refurbished 512GB unit as soon as I heard they were available. It was delivered about a week later on a Thursday and immediately, we noticed battery life was very poor compared to mine.
Desktop mode showed battery health at 17%, and so by that Saturday, it was packed up to be sent back. Ended up going with a new unit instead, so your story sounds a lot like ours, sadly.
Please let there be Media Delete capability for Roku clients, soon. It’s the only thing missing for the wife and I. It’s incredible without this feature, but would be even BETTER than sliced bread with it!