Boardman,
Your post was addressed to sondriven, but I was the last one in, talking about my problems getting the Y-insert working...so I'll jump back in. Ffmada was the one who suggested in the post before mine that the DPS auxes could be used as inserts, this method wasn't even on my radar, so I decided to try it with no luck.
RE: the type of cable, I am indeed using an official Hosa fx insert cable, with the Y ends marked 'tip' & 'ring'. I've covered the obvious bases I think -- turning off the internal FX corresponding to the send I'm using, and so on. Reading the aux return meters, I do not seems to be getting any signal back into the DPS. Like I said in my previous message, I've gotten the 2 cable (aux-->fx, fx-->input) configuration working succes.
I'll give it another try tonight before I turn in, but I wonder if this is something enabled in later revisions of the DPS software. Out of curiosity, what version of the software are you running? I would be really interested in hearing from anybody who has gotten this configuration running with V1.11, which is what I'm still running...
JN