Had a bit of scare last week with my 5010.
Projector started with the high fan noise, this has happened before but I just let it run it's cycle and it usually starts up, however this time the fan was running at an unusually high speed for ages and ages then it just stopped and the red lamp led lit up. I decided to switch off the PJ for a minute then switch back on, the PJ then started OK.
I put a 3d movie on and tried to switch to 3d mode, I then heard a horrible grinding noise and then up popped a warning on screen saying 'Cinema filter error call service'. I switched the PJ off and left it for a minute and switched back on. Again I heard the grinding noise and this time the PJ didn't start up at all, just the fan. Turned off the PJ and turned back on several times and still same thing each time.
Bummer, I thought something had failed inside causing all these problems.
Anyway as a last resort I decided to load up the latest 1.09 firmware. Put the PJ into update mode and uploaded the firmware successfully. I then switched off the PJ and then back on. This time both red lights on the PJ were lit. Oh dear I thought, but then realised I'd left the USB cable attached, so switched off, unplugged cable then switched back on and bam, back in business. The PJ started up normally and no grinding noise and the PJ has been working fine since...phew.
Not sure if the firmware upgrade fixing it was a coincidence as the software on the PJ had got itself in a tizzy or something. But hope it doesn't happen again.