the only answer i can give you is i dont know. SP for me sets on very suddenly. There isnt much of a time line to go by. You were seeing HI, and you sounded pretty relaxed. so those are some good signs, but you could have been 1 sec away, or 20 min. away and had the same signs.

Did you lose your train of thought much? or did the stuff on your ipod sound distorted at all? those might have meant you were closer.