DAQ time lag

Hi, 
I'm running a photosensor which detects drops.  This requires data to be collected with 5ms gaps in collection or better.

I'm using finite sampling on Labview 2009, taking 100 samples at 1kHz in a While loop.  I've tried DAQ assist and DAQmx.  With either, the DAQ loop takes ~125ms to run.  Collecting fewer points still has a roughly 25-30ms lag.  I've confirmed the processing loop is not causing by problem by only running the DAQ loop and I still get the lag.  What is the best way to collect the data to not miss any drops?  My DAQ is an NI USB-6212.

The DAQ loop is on the bottom of Check Valve Prelim Rate Test.

Thanks!

--nate