I've got the same projector and have occasionally had the same issue. In my case, it has to do with a loose HDMI cable. I've got a not-that-expensive 25' cable from my receiver to the projector. For some reason, the receiver end tends to come loose (probably because it's not yet in a cabinet and I keep moving stuff around it). If the connector is even slightly misaligned, I get a colored haze. Purple is the most common, but I've also had yellow. If it gets really misaligned, I either get pixellated static or no signal. To fix it, I just unplug the cable and plug it back in (at the receiver), making sure it's snug as can be. I've been thinking of ways to make it a little tighter (aside from buying and re-running a new cable!), but have so far come up empty.
Cheers,
Kevin