I'm looking for some help about a latency problem with midi processing using pd under Windows XP.

Here is the point : I'm using pd to process some midi data coming from electronic drums. These data are then sent to another software (e.g. Nuendo) thanks to virtual midi ports (MIDI Yoke). Assuming '<->' is a midi connection (virtual or physical), it looks like,

drums module <-> Sound Card (Midi Ports) <-> Pure Data <-> Midi Yoke <-> Nuendo

The problem is that pd introduces some latency... and pd is definitely responsible for that... because the following setup does not introduce latency :

drums module <-> Sound Card (Midi Ports) <-> Midi CC <-> Midi Yoke <-> Nuendo

(Midi CC allows to connect virtual ports between them)

The last point is that latency does not seem to be sensitive to the patch. I tried a simple midi thru patch and another patch with complex treatments and nothing changed...

Help