ping problem with the rcm3000


if i ping to the rcm3000 via a crosscalbe everything works fine.
But if i do this via wireless AP and Antenne on the bord the ACT turns on and than goes out together with the LNK led.
If i do not ping the LNK led is green! only when i want to communicate to it, they go out.

Does anybody have any idea what this could be?
I’ve teste the AP and antenne and they work fine

thx in advance