Constant WAN (light) activity but nothing in the logging trap (even on debug)

[alceryes3]

ASA 5505, 9.1.4

I few days ago I noticed continual activity on my WAN interface light. It's definitely coming from the outside as my cable modem activity light is also blinking consistently. This has happened previously with brute force attacks on my FTP but this is different as I don't see anything in the logs, even on debug mode.

I am very much a novice at ASA and IOS configurations and am wondering, if I'm doing certain policy-map inspections (ICMP), will they still show up in logging? It doesn't seem that any of this 'activity' traffic is making it's way to my inside interface as 99% of the time my WAN port is the only one blinking.

TIA!

[Philip D'Ath]

Install WireShark onto a machine.  Unplug the ASA and plug the cable modem directly into your machine (assuming it is just running normal IP and not PPPoE or something else).  Start WireShark doing a capture, and see kind kind of traffic it is.