AirPlay not working with my home wifi, but is fine at work. Suggestions?

Not sure if this will resolve your problem but I had same problem. The airplay button would not show up on my iOS devices particularly my iPhone and I noticed the remote app was not working correctly also. For airplay and the remote app it wax a hit or miss the later being the most. The thing was my remote app usually never acted up before but than in remembered that I recently changed my router from an Apple Express to an Extreme. I had my Express set up in manual mode and I selected channel 11 manually. But when I set up the Airport Extreme I left the router in the default mode of "automatic". Upon changing the Extreme back to manual and selecting my own channel, everything has been great! So if most of you are like me and live in an Apple ecosystem and have Apple routers you may want to make sure the router is not set in automatic. I believe this to be what is causing problems.

Make sure all of your devices at home are actually connecting to the same network. The numbers in the IP addresses should be the exact same before the last dot. Also, some non Apple routers can do certain things to block what AirPlay uses to connect. Some have reported turning off QoS made it work for them. You could also try just rebooting your router by unplugging it.

Some routers have a "Quality of Service" feature that's supposed to favor certain type of traffic on your network over others. Say for instance to favor VOIP calls over downloads or video streams. That sort of thing. I've seen it reported that it might be causing problems with AirPlay but could just have been coincidences.

I use a LinkSys router and was experiencing a similar issue where my iPad wasn't showing the AirPlay icon. I tried changing the Wireless Network Mode (under Wireless > Basic Wireless Settings) from "Mixed" to "G-Only" -- and voila! I now have AirPlay. Hope this may help others if they have a similar router/setting.

I have tried this as well. It only been a day and so far so good but sometimes it takes a few days before my icon disappears. Have you found the problem return since youve changed this setting on your router? I use a Netgear router but the theries are the same.

Well it's now been over 5 days and my Airplay icon has not disappeared once off either my iphone or my wife's. It normally would have by now. Touch wood, but I think this is the answer to the problem.