well, i'm digging into stuff i haven't thought about for years, but here's what i think...
you don't need an adapter to go from stereo to mono. basically, on a stereo plug, there are three contact areas - the tip, a small collar, and then the base of the jack. i don't know which is which, but one is the left, one is the right, and one is the ground. when you plug it into a stereo input, there are three contacts inside that touch each part.
if you plug a male stereo into a female mono, there should only be two contacts in the female jack. one should still hit the neutral, and one should hit either the left or right. it might not sound pretty, but you should get SOME sound.
i think the problem is that a mic's signal is MUCH lower than a line-level, as your ouput from your source should be. in other words, the mic input is expecting a much lower signal strength than what your giving it.
now, i'm not sure if your computer is shutting things off since the voltage coming in is too high, if you've (possibly) damages it, or something else, but i really doubt you can get it to work, without something to drop the signal strength down. [ July 22, 2006: Message edited by: fred rosenberger ]
There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors