I took a look at your VI and noticed that you are specifying your device through a constant on the block diagram. Have you seen this KB? It mentions that error 9320 sometimes occurs when you specify the incorrect device. You mentioned in your post that you have swapped hardware, so your device number may have changed. You can use Measurement & Automation Explorer to determine the device number of your DAQ card by expanding the Devices and Interfaces folder and looking in NI-DAQmx Devices (if your DAQ card is a DAQmx device) or in Traditional DAQ Devices folder (if your card is a Traditional DAQ device). Please let me know what DAQ card you are using and if changing the Device Number helps.
Nicholas B, National Instruments