What is the optimal AirPlay configuration when using two Airports Express? I have two Airport Express base stations in my abode:


an AirPort Express 802.11n (2nd Generation) – A1392, and
an AirPort Express 802.11n (1st Generation) – A1264


Call the former (the newer model) A and the latter B. They are in the following configuration: A is wired to the cable modem and is the primary wireless base station; B is in a different room, configured to join that wireless network, and is connected to a stereo system. The goal of this setup is to provide the fastest possible internet to laptops, iPhones, etc. while enabling AirPlay music streaming to the stereo.

Unfortunately, I can't run a long ethernet cable between rooms (in a practical manner) – though if I could, of course I'd be able to remove one of the base stations from the setup entirely. Naturally, I would also like to keep the two base stations as part of the same wireless network, so I can use the internet while also playing music over AirPlay.

This Apple Knowledge Base document suggests that B joining A's network (the current configuration) is better than B extending A's network, for "overhead" reasons:


  Connecting to an existing Wi-Fi network as part of a legacy WDS or Extended Network
  
  AirPort Express extends Wi-Fi network range and streams iTunes music simultaneously using Extended Network for AirPort Express with 802.11n, or legacy WDS with AirPort Express 802.11g from another Wi-Fi base station.
  
  Due to the overhead required for this configuration, you may expect AirPlay drop-outs such as intermittent loss of audio.


I'm not sure if that's really an issue since they're both 802.11n routers. Then again, B is a "Draft 802.11n" device. I'm not sure how that affects things.

Problem

Streaming music from a laptop, regardless of the source (iTunes, Pandora, etc.) tends to stutter, intermittently cutting out for a few seconds. This seems to be a common issue. I haven't tested whether higher-bitrate songs causes the audio to cut out more frequently.

Question

How should I configure my wireless network(s) to reduce, and ideally prevent entirely, the audio from cutting out when I play music to my stereo using AirPlay? All of the hardware involved is Apple-made, so I can only imagine this is not a terribly exotic setup.

I haven't tried swapping the base stations yet. I'm willing to do that, but I'd really prefer to avoid trial-and-error with every combination of physical and software configurations. What can I say – it's not exactly my idea of a fun weekend project.

I have tried setting up a 5GHz wireless network on A, and having B join that, but it doesn't appear that B can. It looks like A1264 can broadcast at 5GHz, though I don't know if that implies it should be able to join a 5GHz network. Either way, it sure doesn't seem to be able to join my 5GHz network.

Potentially relevant details


There is a printer connected to B with USB.
No computers in the room have Bluetooth enabled, though there is an iPhone 5 and Pebble watch that are paired with Bluetooth. I mention this because BT supposedly can cause problems with AirPlay.
Funny story.

Switching B from "Join a wireless network" to "Extend a wireless network" seemed to fix the problem instantly, despite the caveat in that Apple KB doc.





Two days later, the problem has returned. It seems that I can deliberately exacerbate the problem by using extra bandwidth, such as by running a speed test (over WiFi, of course).