Can't talk to digital module with old cRIO

[LukeS]

I am using the old FRC cRIO, and am having trouble getting it to talk to the digital sidecar, and probably the NI 9403 digital module itself. The module shows up as OK in the 2012 imaging tool. The cRIO is running "FRC_2012_v43".

I have the module in slot 2 of the cRIO, but have also tried slots 4 and 6. Sometimes, and I can't figure out the pattern, I get an ArrayIndexOutOfBoundsException from DigitalModule.java:68.

I am using Java, and am testing the module with

public static final DigitalInput dio13 = new DigitalInput(2, 13);

(I have a switch plugged into that channel)

On bootup, this

[cRIO] Digital module 2 is not present.
[cRIO] Digital module 2 is not present.
[cRIO] DIO LoopTiming: 260, expecting: 261
[cRIO] Digital module 2 is not present.
[cRIO] Digital module 2 is not present.
[cRIO] Default IterativeRobot.disabledInit() method... Overload me!

and can only get false from the switch.

Any help is greatly appreciated.

[edit]More info:
On the digital sidecar the BAT, 5V, and 6V LEDs are all on. When disabled the RSL does a slow blink, when enabled does a long-on, short-off blink.