No computer has midi ports, not that I've ever heard of anyway. Everyone just uses a midi to USB interface, as you seem to have, so the connections go:
[Synth midi out] --> [Midi interface in]
...............................................................--> [USB on computer]
[Synth midi in] --> [Midi interface out]
It does sound like a driver issue.
If you're doing a bit of soldering work to replace/repair a pick-up, or a knob, or you're DIY'ing an FX pedal, or, er, something else, and you need some wire, or cable, what do you use, what's it called, and where do you get it from?
If you don't get anyone local to pick it up, which would be best, I would love it as a project (I'm in London), and would of course make a donation to this place.
But let's hope you get lucky with a local.
I sometimes put things up for sale with outrageous prices, just to see if anyone will go for it, and sometimes they do. Things are worth what people are prepared to pay for them.
I use these:
[url="http://www.7dayshop.com/power-stations-9v-6lr61-mn1604-pp3-e-block-high-power-alkaline-batteries-amazing-value-10-pack?q=9v+battery&dir=asc&limit=all&order=price&ajax=1&sl=sl"]http://www.7dayshop....ce&ajax=1&sl=sl[/url]
But that's because I'm cheap.