airport express DOSing modem

my 2nd gen airport express seems to be spaming my modem i have to reboot the airport a few times a day or i have no internet connection

i have done ping tests to my modem and it times out when the airport is connected to the network but not all the time is there a way to see what the airport is doing on the network? as its only just started to happen in the last week? any help would be great

Thanks