Dendrobium help needed!!!!

[ChasWG]

So I have owned this Dendro. Norma Jackson x Den. 'Pink Sunshine' for a few months now and it has done nothing. No growth, no spikes, nothing.

Well, not nothing exactly, it is now loosing leaves. It lost one leaf a few weeks ago as it shriveled up and turned yellow. Now it's happening again to the other leaf on the opposite side. And three other leaves are starting to shrivel a bit too on another cane.
What is going on?





Here's a picture of the good leaves on the other two canes



Those leaves are more rounded that the longer spear shaped leaves that are dropping.

What's going on with this plant? This is my only Dendrobium that I own. It gets watered when it is dry, maybe once a week. Is that too little? I thought these guys like to dry out some.

Any help would be much appriciated as I would hate to loose this plant.