Just an FYI for those dealing with the Rs540 DI issue. I just got my projector back from service. Had a long and very helpful conversation with the tech that worked on it. He ended up replacing the lamp iris on my unit but not the lens iris, which he said was working within spec.
The way it was explained to me, even though the lamp iris is manual, it still affects the movement of the lens iris as the two are working in tandem. He said when he disassembled my unit, he could manipulate the lamp iris by hand and found that it was sticking in certain positions, and then later eventually springing back into place. So essentially the lamp iris being stuck was preventing the DI from operating correctly, and then it would eventually start working again when the lamp iris unstuck itself.
I can confirm that moving the manual iris through the steps in the menu is a bit smoother now.
This might explain why some people were finding that the issue went away after they ran the manual iris through its range a few times.
I’ll report back if the issue occurs again, but I’m cautiously optimistic that they’ve resolved it, and for the specific issue I was experiencing, it was in fact a hardware issue.