I'd tend to voice the "h" in cniht as a gutteral, but that's by the by. Deloney was writing in the second half of the 16th century (the date of the events he was describing is beside the point), but "Raedwulf"s suggestion doesn't seem unlikely, even if based on much earlier usage; though the "i" may have been slightly elongated: not as far as "sween", but in that direction. Mind you, that's based on my recollection of being taught approximate "period" pronounciations as a student 30 years ago. Might be way off.