[LAU] When would ~/.jackdrc not be honoured???

[Mario Lang]

Hi.

I have a strange situation.  When I launch scsynth manually from a
shell,
it starts jack according to my ~/.jackdrc and everything is fine.

If I call basically the same scsynth command as a subprocess from
a program (written in Haskell) scsynth seems to launch a different
jack, which fails claiming it can't read hw:0.

So my question is: When exactly would autostarting jack *ignore* my
~/.jackdrc, and why, and how do I stop it from doing so?

-- 
CYa,
  ⡍⠁⠗⠊⠕