I am back to getting 90k immediately on login on my main (Balmung). I hit sprint, the animation occurs but the buff doesnt apply. About 10-20secs later, DC + 90k.
I can log in to a new toon on a diff server (Malboro) just fine.
Issue definitely isn't ISP based if it's singling out characters. I have read cases of people with the same issue being able to play different toons on the SAME server just fine.
Damn Square Enix, when you make a bug you go all out