They certainly do "go to sleep" when unused, or when you happen to wander away too far from your computer. But they are easily turned back on again with the small button on the right ear cup. I really appreciate that a voice tells me when I turn these headsets on or off , as well as informing me that I'm connected or disconnected to my computer. I was a bit skeptical when I made this purchase, but now I'm very pleased with them. For me they are quite comfortable and completely surround my ears, they recharge easily from my computer's USB port, and the battery seems to last a long time. I've never had them run down, and I wear them much of the day. I recharge every couple days or so. Getting them connected to my home-built Win10 desktop machine was a bit of a chore, but that was because I had to find settings on the computer and activate them, while the headphones themselves connected right away once the computer was set up properly, and now they connect the moment I turn them on.