1)Upgrade the firmware and drivers for the new products
2)Have either devices moved slightly - anything in the line can affect the signal - if you can get a line of site through windows that is perfect, otherwise as few & thin walls as possible, no metal objects etc ect.
Much better to gain a line of site rather than a high gain antennae, although it would help too.
3) Try changing the channel used by the router - 1,6,11 are the 3 to try first, although it is probably on 11 as default.
4)Various other gear can affect the signal, microwaves, dect phones ...