I've had issues with my bulb life and have had many communications with Sanyo Service about this.
This is something they told me to do once, and since I just did it, thought I would post this tip.
Granted you should you keep your filters clean. I check/clean mine every two weeks. I don't have a dirty house, but...
Sanyo Service told me once to vaccuum the air intake outlets since dust/dirt will accummulate there and cause higher bulb temps which will reduce the bulb life.
Since I was told this, I have made this part of my cleaning routine and have had MUCH better luck with my lamp time. My bulbs don't burst and I get much better lamp life. I don't have a newer unit, but I'd recommend the procedure, based upon my experiences. They don't tell you this in the manual. My bulb life DOUBLED after doing this.
So, about every two weeks, I unhook the PJ, turn it over, and place a vaccuum over the air intakes and suck out those areas for a while.
Your mileage may differ, but this has saved me quite a bit of money, based upon my bulb mileage prior to hearing about this.
In fact, the infrequent dust bunny has ALSO been removed doing this.