I have a very odd problem and will try to explain it as best I can.
Setup: SA540 (fw 2.1.71) with pretty basic configuration, no VLANs or QoS. Wireless APs and 3 large Netgear gigabit switches plugged straight into the SA540 LAN ports. Wireless APs are: 1 Aiport Express, 1 Linksys WRT54GL, and 1 Asus RT-N56U.
Problem: network speeds (transferring files) to the servers from wired and wireless workstations is very slow, around 200kBps.
Resoultion: plug the wireless APs into the Netgear switches instead.
Notes: any connection through each of the wireless APs was very slow, but not a signal problem. Even when plugging straight into one of the wireless AP's inbuilt switches, the speed is slow. Only when unplugging these APs from the SA540, and plugging the APs into any of the Netgear switches, does the transfer speed go back to normal even when the traffic still goes through the SA540 to reach the destination.
I don't understand why creating this extra hop between switches would help, and why plugging the APs directly into the SA540 is an issue.
Can anyone help? Please ask for any more details if it will help.