6-month old thread. We usually lock these threads if that's the case, because firmware and hardware revisions can change the nature of the game.
That being said, I'm content to leave this one open, however I suggest you contact CS in regards to the problem. They'll run you through a few hoops to try and nail down the issue that might be causing excessive heat, and if it so happens that it is the Roku at fault, they'll be in a position to evaluate whether or not an RMA is in order.
In general, because of the low wattage used, overheating is not a widespread issue, and I don't know of a single case through CS that has ever been reported in which a unit did, in fact, overheat, to a danger point. I personally have a Roku 2 HD (one of the first generations, I believe), and I'm not experiencing this at all, despite its very prevalent use in my home (moreso than the XS).
I'd be more inclined to think it was something within your setup (location, nearness to other electronics, lack of airflow, or even a bad power strip/surge protector) that would be causing the problem.
C. Shawn Smith
Forum Community Liaison
The Cosmos is all that is, and all that was, and ever will be. -- Carl Sagan