We have a PIX 525 that we replaced with a ASA5500. Our F5 connects directly to the 5500 but no communication occurs between the F5 and the ASA. I checked the F5 ARP table and it doesn't even have the mac address of the ASA. We tried both straight-through and cross-over cables. Then we put a switch in between them. We changed duplex and speed settings all without luck. Anybody else run into this?