Using output compare on an XBee ZB Programmable S2B

I’m having trouble using the output compare function of the xbee library. I’m setting a timeout of 10 uS like this:

ocompare_config(ocompare0, 10, 10, OCCOMPARE_TOGGLE);

but the edges that come out aren’t 10 uS apart, they are 2.7 msec. The xbee programmable is the 32K variety, and I have the clock set to 48 MHz in the project configuration.

It’s not clear to me from the documentation whether or not I need to keep resetting the timer in the interrupt service routine, so I tried:

void ocompare0_irq(void)
   occompare_set_timeout(occompare0, 10);
   /* toggle a GPIO pin to make sure it's working */

but that had no effect at all (still 2.7 msec) other than proving to me that the interrupt service routine does indeed fire.

What am I doing wrong?