yyz - Bill didn't actually make a very firm recommendation. He said that this unit, the SCD-1 has a thermal dissipation problem, which he elevated to a design flaw that shortens its life. He acknowledged that most audiophiles leave their gear up 24/7, and that is generally best because thermal cycling is what does the damage. When I probed, he said that knowing what he has seen over the years, he would probably take a hybrid approach, leaving it up when in steady use, but shutting it down when it would be unused for awhile. He didn't specify how long awhile is. I would conjecture that a couple to a few days might be awhile.