Hey there Know it alls I have a quick question.

My ISP changed my dumb cable modem for a Modem/Router combo unit. I plugged it in to my fancy pants router (BUFFALO AirStation Extreme AC 1750) and didnt make any changes (because lazy). Its working fine but now my NAT in games has gone from Open to Moderate. Should I have disable something on the modem or router instead of being lazy and just plugging it in without changing anything?
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