I have one too--Lava Burst 'Puanani' AM/AOS. I've had it for two years.
It's in a media of rocks, clay pellets, and bark. It blooms twice a
year. I treat it like a cattleya. It goes outdoors for the summer. In
winter, it is in a south-facing window and also gets 400 watt MH light.
It gets watered and fertilized like a cattleya, and no special
treatment. My guess is that your plant is getting used to S/H. When it
finally blooms, it will do it big time.