Unknown channel or repeated capability name N6700

I am using the IVI-C driver for the N6700 power supply (http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=7695). I am using LabWindows / CVI to create a DLL and TestStand to controll it. I have successfully used this driver to intialize, power up, readback values, power down, and close. However, I am  having an intermittent problem revolving around the error "Unknown channel or repeated capability name." It occurs randomly on any function call.

I attached some of the files I'm using for reference.

Any Ideas?