Th eonly thing I can think of is if its related to comedy.Certain characters say something like an elongated 'I' which I would spell as 'aiiiii'(like eye) which is menat to be a long drawn out 'allright' which refers to saying Im alright or yes.
I don't think so. Again, it's made-up so no RIGHT or WRONG answers per se -- could be that the person was trying for something and didn't quite convey it clearly.
But to me its more of an "eeeeeeeeYAH!" Something that starts more contained and then bursts out at the end.