I am running Windows on an Apple laptop and all works fine with the DPSK. It's mac address is ab:cd:ef:12:34:56 (for example).
When we plug the unit into an Apple thunderbolt display, the wireless ceases to work. The mac address then shows as ac:cd:ef:12:34:56 (notice the single digit change in the first two digits). So I create a new DPSK for this one. It connects.
Disconnect, reboot and the internal wireless will not connect.