Please try this method of setting up your NICs to see if it makes any difference.
Disconnect the ethernet cable. Delete all NIC entries through PCC.
Create a wireless NIC, choosing to specifically connect to your router which should be listed.
If it is not listed but you only have a manual option, then please check that your router is issuing an SSID and start again.
So select your router from the list instead of manual option. Accept the defaults until you come to the choice of allowing roaming or not.
Select no roaming. Tick the other three options.
Now your wireless should connect.
After confirming the connection insert the ethernet cable.
After some little time you should get confirmation of this.
If the connection for the wired NIC does not set up automatically, then go to PCC and set it up.
From there plugging and unplugging the ethernet wire should cause the connection to switch from wireless to wired and back again.
One rider ..... my wireless NIC is supported natively ==> I do not have to use ndiswrapper.
If yours is different then that may affect things, or if you have been using some other means of setting up the NICs that also may have an impact.
I suspect the problem may have to do with the settings in the router ..... not broadcasting the SSID might create the problem.