<p>A couple weeks ago, I posted about my D750 locking up and refusing to be turned off, wondering if anyone else has had the same thing happen. Some responded (here, and on Nikonians) that they had. One person suggested that I send it to Nikon for evaluation, since it's under warranty. I took that advice and got the camera back today. It was there for about ten days (seems pretty quick to this former Pentax user); the paperwork is a little hard to decipher, but it appears they replaced the "memory compression", whatever that is. They also replaced the rubber grip and the "rewind side" rubber - ?? - I don't recall anything being wrong with those, but I won't argue. They also checked the shutter, the metering, and the AE operation. It works fine, of course. I think the moral here is this: if you have a camera under warranty and it acts up, send it in. It seems they WON'T just send it back saying they couldn't find anything wrong with it.</p>