I purchased new injectors that claim to be 802.3af/at because I was told I needed one in order to enable eth1 on a device (without having to plug the router into the wall). The injector I purchased is a 48v 35W injector, which according to specs should work. But eth1 is still disabled. Is there a certain injector that I need? Is the fact that it is compatible with either standard the problem? What do I need to get? I still have time to return these and get something else.