I had problems too, trying to start pd 0.38test10 with an emagic emi 2/6.(Won't run at all). Seems that the portaudio code of pd is less than optimal. Not sure if the way to solve this is writing native ASIO code, as it is done currently by Tim and Tom (;)), or to fix the portaudio stuff.
i'm not familiar with the hercules dj console ... but i suppose, it's common for usb devices to work with a block size of multiples of 441 (at least with my old quattro that didn't run with portaudio, too)
for these devices, i still have some problems to reduce the input latency with the native asio implementation ... you could at least try it and give me some feedback ...
in addition to that, i'm currently working on the main scheduler ... it would reduce the latency even more, if we compute the dsp at the time of the asio callback ... (hopefully i can add it to the cvs in a couple of days)
cheers ... tim