Hey! Can you verify that you don't have any SSIDs configured to use 'NAT Mode: Meraki DHCP' in the Wireless > Access Control page? If that AP is broadcasting a NAT Mode SSID, then it will NAT all of the traffic coming from the client's IP to its own IP address on the LAN. This could explain why your IDS sees the APs IP address. If that's not the case, Philip's mention of a false positive is possible, since the AP will not pass traffic (using its own IP) on behalf of the client unless the NAT Mode SSID is configured.
... View more