[General Maximus]

firstly dude, when the shub is in modem mode your laptop isnt the router, it is just a device directly connected to the modem and heading off to the internet and thus no routing is occuring which avoids all the hassel of the shub. You can do one of two things; a) try putting your ps3 in the shubs dmz or b) avoid all future problems by keeping the shub in modem mode and buying yourself a proper router so you dont have to suffer these trivial problems.