Passive Torpedo Problems

[Soundman]

I'm hoping someone can help me here. I have launched many passive MK-48s in passive mode and not one will hit a target. So I tried an experiment with truth turned on and wire guided the thing directly to the target and nothing. And yes, the fish were enabled. I have even guided the torpedo and watched a torpedo go directly through a submarine. I first thought maybe a problem with a patch or a bad install perhaps. Re-installed and the same thing happens. Hmmm?.....O.K......Re-installed with no patches.....same thing. I even went as far as thinking it was an "XP PRo" thing..Nope, I tried it on my old computer....Same thing.....Oddly enough, I even re-installed Sub Command and even it does it too...I must be overlooking something terribly simple here. My active fish hit nearly every time. I use the same procedures with actives as passives except I uncheck the box. (to select passive mode). Any Suggestions? Thanks!