What's the ambient temperature? Is the Roku on some other device that generates a lot of heat? I haven't seem this behavior, and I have no A/C, but I do most my development at dusk and after. That said, it's been somewhat warm a few times (~80 degrees), and I haven't seen this problem. I haven't seen any overheating issues on my other unit, which is dedicated to normal use, and I've used in MUCH warmer temperatures (> 100.degrees).
-- GandK Labs
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