TDMS Write Function slowing loop

Hi,

I'm counting edges of TTL pulses coming from a photon counting photomultiplier tube module on my PCI-6602. I'm trying to sample at 4 kHz, but at 2 kHz my consumer loop starts to lag behind. Without the TDMS Write Function I can sample at > 4 kHz, so I believe that to be the issue. Is there a more efficient way to write the data or have I reached a limit for writing my data?

Thanks,

Dillon Kopecky