MacBook Pro – No Audio When AirPlay Mirroring to Apple TV

I'm having quite the same issue not with an apple tv but with another stuff provided by my Internet broadband which is doing air mirroring. I have a mid 2013 macbook air and mirroring my screen is lagy.

So I thought the issue was from the router too, but my brother with his latest MacBook Pro doesn't have any lag, it's really fluid.

So I thought the MBA wasn't power enough too handle the real time encoding, but one day while I was mirroring my screen I launched a slide show in iphoto and it was really fluid. Then I noticed when I turn air mirroring on it's always lagy until I launch a video from QuickTime.

So, to sum up - this likely is a software issue since under iPhoto and Quicktime, the MBA is fast enough to handle high performance mirroring of some content. (Or that it lags when it has to both assemble the image to draw on the screen and then mirror it - but when QuickTime or iPhoto take over the entire screen - mirroring can be quite snappy).

First thing I'd check is whether the firewall is enabled on your Macbook and blocking incoming packets. If the firewall is on, try turning it off temporarily for a few minutes to see if the AirPlay icon appears in the menubar.

Next thing to check is whether the devices are on the same subnet. You can find the IP address and subnet mask of your Apple TV in Settings -> General -> Network. And the IP address and subnet mask of your Macbook in System Preferences -> Network -> Wi-Fi -> Advanced... -> TCP/IP. Ideally what you should expect to see is the same subnet mask on both devices (likely something like 255.255.255.0) and IP addresses that are similar except for the number after the last dot (something like 192.168.0.125 and 192.168.0.138).

Those are the two things I'd check first. Check those and let us know how you get on.

Apple have a guide to trouble-shooting AirPlay problems for Macs. There are a few other things that might help too: About AirPlay Mirroring in OS X