If he can't afford to support two families,then he shouldn't have started the second.
It isn't the fault of his first child that he got a felony and made another baby he can't support. Why should that child do with less because of his actions?
He can try to go back to court and have his support lowered,but since $330 a month is minimal support,he might find himself having to pay more instead of less. I doubt the judge will be sympathetic to his sob story.