Ay caramba, for all the time you've put in trying to get that poor old thing not to blue screen your system, maybe check out the price of a brand new MIDI interface with updated drivers.
I like to squeeze the last bits of usefulness out of old hardware as much as the next geek (check sig for proof), but at some point, cost:benefit says that a Midiman UNO goes for around $30.
If it served you for decades, you got your money's worth out of it.
Off the top of my head as a tech, I'd say that it's probably just too slow to keep up with that rocket sled you have it plugged into. It's tripping over its own feet. If there is some way to give it some more buffering on the system side, that might be the answer, but that might also induce latency.