DS and Studio Flash problem

[revphoto]

I just bought my Pentax *ix DS and have used it with a studio flash system attached, connected by a hotshoe PC adapter mounted on top of the hotshoe, for two shoots with no problem. But last weekend, all of the sudden, it failed. The camera won't trigger the studio flash but would trigger a regular Vivitar flash connected by the hotshoe adapter. What seems to be the problem, and how could I fix this?

[jeisner]

I would suggest asking on the dpreview 'pentax slr' forum as I know there are a good number of people there using the D and DS for that kind of work.. personally I have never used the DS in that type of situation so have no idea how to help, sorry...