So far there have only been 6 reports of this issues from 100's if not 1000's of 3010/5010/6010 owners just at AVS.
Even with a replacement, those with this specific issue still have the same problem.
It may be something in your environment that is causing the issue.
If this was a widespread issue, believe me, you would hear it loudly here.
I would look at things like AC power(level and may be hertz, noise).
Any RF in the room that interfere
Make sure the connected equipment in the HDMI chain to the projector HDMI is not configured to send HDMI on/off commands(Anynet, HDMI Link, etc)
May be next time this happens, try disconnecting the HDMI cable from the projector and see if the remote works.