All devices are running DD-WRT v24-sp2 build 21061. All devices are on the same subnet (192.168.1.x) and use the same subnet mask (255.255.255.0). Under "Advanced Settings" on the Wireless->Basic Settings screen, the "Network Configuration" is set to "Bridged" on all devices.
The DIR-825 connects to my Comcast cable modem and serves as the primary firewall, WiFi access point, DHCP+DNS server. It has Operating Mode (Setup->Advanced Routing) of "Gateway" and Wireless Mode is "AP".
The two TP-Link devices are used to give additional wired-only devices access to the Internet. They have an operating mode of "Router" and their Wireless Mode (Wireless->Basic Settings) is "Client Bridge (Routed)".
Everything on the network seems to be working as expected... except AirPlay (and perhaps other Bonjour-related services?). In my specific case, I have an AppleTV connected to the WDR4300 (via Ethernet cable) and want to be able to send it AirPlay content from any wired or wireless device in the house.
There are only two configurations that seem to work:
1) AirPlay works between the Apple TV and any device which is physically connected to the WDR4300 via Ethernet cable.
2) If I connect the AppleTV to the DIR-825, rather than the WDR4300, then all devices on the WiFi network can see the AppleTV. In this configuration, wired devices connected to the WDR3600 (and presumably the WDR4300) cannot see the AppleTV nor can the AppleTV see any of these devices.
It feels to me like the multicast DNS requests/responses used by Bonjour or AirPlay aren't being properly forwarded to wired clients connected to a client bridge device. Is there any way to make this setup work? Is this a problem with my configuration? A bug in DD-WRT?