someone else. that s why we wanted a brand- new system. reporter: that revelation is the latest fallout from our exclusive report this week about a serious construction issue that could add months and millions of dollars to the beleaguered project. the valley transportation authority discovered in june that 1,100 used routers and switchers had been installed in the rail line s communications, computer and security systems. it s just like buying a new car versus a used car. you essentially don t know what that used car has been exposed to. so you buy a used router, you don t know what it s been exposed to. you don t know what security upgrades have been made to it. reporter: the vta says three companies illinois based aldridge construction, their partner san jose rosendin electric and subcontractor hsq technology were responsible for buying and installing the used equipment. the companies say they are working closely with vta to correct the problem, a problem that if gone undetect