Mountain Lion - Airplay, no audio

I had the same problem, mid-2011 Macbook Air, Gen 3 Apple TV. My router is an 02 Wireless 2 (in the UK) which does not allow you to change the band.

Luckily for me the Apple TV is right near the router so I just plugged it in through an ethernet cable instead, which worked.

I have 2nd gen AppleTV (720p) and a Mid-2011 Macbook Air running on an Airport Extreme. The AppleTV is connected by ethernet.

I was able to do AIrPlay mirroring with video AND audio, but if I tried to do audio only, the screen would blink momentarily and then it would blink off and wouldn't work.

I switched the Airport Extreme to 5G and now it works. This isn't a permanent solution for me because I have older devices that need the other freq.

I had the same problem. AppleTV 3rd generation Early 2011 MacBookPro 13 inch.

I could see my AppleTV in my audio devices, but could not select it as an output. However, I was able to use Soundflower as the output feeding to the AppleTV to get sound to work.

I was on a Meru network. I have no idea what frequency the routers use.

Has anyone had the same problem and fixed it using a BT Home Hub 3 router?

Thanks

Just restarted WiFi on my macbook and it resolved the issue!

I had a similar problem today when I powered on my windows machine, the time capsule backups and file sharing started to be very slow, then powered off the windows machine, restarted wifi on mac, and speed went back to normal.

Mid 2011 macbook air, 3rd gen apple tv.

if i option click sound, and select apple tv ... it works maybe 50% of the time. As well, I've found restarting my computer resolves the issue.

Mid 2011 MacBook Air, 2nd gen AppleTV. Video AirPlay works everytime, but audio (either with video or on its own) works maybe 25% of the time at best. Restarting the AppleTV and/or the laptop helps, but the problem comes back pretty quickly.

A feature of the problem is that when I try to select the AppleTV as the sound output device it's briefly visually selected while I hold down the mouse and then immediately flicks back to the internal speakers.

My AppleTV is connected over WiFi, while my MacBook is connected via Ethernet so I don't *think* this is necessarily a problem only related to the devices being on different wireless frequencies. I just tried connecting my AppleTV to the 2.4GHz network and it didn't help at all. It could definitly be a problem relating to routers in general though. I'm on a Cisco LinkSys E3200. More discussions:

https://discussions.apple.com/thread/4156937?answerId=19599923022#19599923022

https://discussions.apple.com/thread/3622348

Basically audio AirPlay on Mountain Lion is flakey as **** and Apple need to fix it.

It isn't a wifi issue between 2.4 and 5 GHZ. I have an last gen Airport Extreme base station and a 3rd gen apple TV and a 2011 Macbook Pro. They are all on the same WiFi frequency and I see this issue sometimes.

I found this elsewhere on the internet. Worked perfectly.

This is an issue with Core Audio on OS X getting caught in some sort of resource availability loop with Apple TV. If you restart Core Audio on OS X and make sure there are no other iOS or OS X devices requesting access to the ATV, then it'll fix this issue. To restart Core Audio you can either:

Method 1:

1) Open Activity Monitor (control + space then start typing "activity monitor")

2) Find the process coreaudiod

3) Select and quit

Method 2:

1) Open terminal

2) type command: sudo killall coreaudiod

3) enter admin password and confirm

OS X will cycle Core Audio on and off and voila- your audio streaming will work again.

There's no way to prevent this issue right now. It's a Mountain Lion bug, I think because I can swap control between my iPhone and iPad without any issues like this coming up.

BeenJaminRocks, Thanks for sending me down this path. Choosing either 2.4 GHz or 5GHz worked for me.

Click on

BeenJaminRocks wrote:

Click on the AirPort status icon in the menu bar For available networks.

Mine shows AirPort Extreme and AirPort Extreme 5GHz.

You may not have the 5GHz option it needs to be setup in AirPort Utility.

Go to Utilities, AirPort Utility, Click on the Airport Extreme then edit.

Click on the Wireless tab then Wireless Options.

If 5GHz is not checked then you do not have 5GHz enabled.

I would not suggest enabling it if is is not because using the 5GHz Network is when my sound did not work.

Mine shows AirPort Extreme and AirPort Extreme 5GHz.

You may not have the 5GHz option it needs to be setup in AirPort Utility.

Go to Utilities, AirPort Utility, Click on the Airport Extreme then edit.

Click on the Wireless tab then Wireless Options.

If 5GHz is not checked then you do not have 5GHz enabled.

Restarting wifi worked for me.

I am not connected by wifi at all, all ethernet connections and I had this exact issue. I followed the instructions for core audio and hey presto back working. But yes, last week working, this work not, but this did fix it ftb.

How do I check which band the AppleTV is connected to and change it if need be? I went through all the menus on it and don't see anything about 2.5 vs 5 Ghz. I'm using a TimeCapsule as my router, fwiw.

Hey, you should try bjdku's solution above. Kill the coreaudiod process. That's what works for me when AirPlay stops working.

I think the wireless network frequency is possibly a red herring ... but if you want to test it here's an answer to your question. There's no option on the ATV to switch between wireless frequencies directly, instead you need to connect it to either a 2.5 or 5Ghz WiFi network. Some routers broadcast both frequencies under the same network name, others broadcast seperately. I'm not sure about the TimeCapsule. You should dig into your router's options/menus and try and understand which frequency your router is using and if you can tweak the settings etc.

Well, I don't even have the "coreaudiod" in my Activity Monitor (in Swedish here)

MacBook Air -12, 10.8.2. But it exist on my MacPro. Strange...

Make sure you have "All Processes" selected at the top of the window near the search/filter field. (sorry I do not know Swedish)