Hi,

We have a Lync (Skype for Business 2015) environment using 2 servers.

One front-end and one edge.

All seems fine and windows clients can chat, do audio and video both inside and outside the lan.

Mac clients can only chat. When they want to participate in audio or video it tries to connect and fails.

Nothing much on the log side.

Any known reason why a mac client can't do audio/video when windows clients can?

You should run a wireshar trace to see what is happened.

Have you activate the Lync for Mac log?

Maybe this link can help?

https://kb.iu.edu/d/bave

Hi Avater,

You might try the following suggestions.

1. Install the latest update of Lync for Mac 2011.

https://www.microsoft.com/en-us/download/details.aspx?id=36517

2. Use a certified device to test.

http://partnersolutions.skypeforbusiness.com/solutionscatalog/personal-peripherals-pcs

3. If your preferred device was not automatically set as the default audio device when you connected it, you can change it by clicking the microphone icon in the lower left of the main Lync for Mac window, and selecting your device from the pull-down menu.

4. If you are having audio problems, and you can't resolve them within the Lync for Mac client, you can specify the input and output devices in your system sound settings:

   a. Open System Preferences and select Sound.

   b. Select the appropriate settings for "Output" and "Input".

Best regards,

Eric

Thnx for the replies sofar.

The problem with the audio/video is not that you can't hear or see anything.

The problem is that when you start an audio or video call it says "connecting" and after like 10 seconds you get call disconnect, (network error).

This only happens with the mac client (fully updated to the latest version). The windows client works fine (lan/remote/mobile).

De Skype for Business Server sit behind a Cisco ASA. It might be an open port problem, but then I would expect the windows clients to also fail.

Hi Avater,

Apologise for my misunderstanding.

Since the issue only happens with the mac client, I suggest you can try to turn off the firewall of MAC OS.

OS X v10.5.1 and later include an application firewall you can use to control connections on a per-application basis (rather than a per-port basis). This makes it easier to gain the benefits of firewall protection, and helps prevent undesirable apps from taking control of network ports open for legitimate apps.

Use these steps to disable the application firewall:

1. Choose System Preferences from the Apple menu.
2. Click Security or Security & Privacy.
3. Click the Firewall tab.
4. Click "Turn Off Firewall" to disable the firewall.

Best regards,

Eric

Hi Avater,

Im writing to follow up on this thread. Do you have any updates on this issue? Please post back at your convenience.

Best regards,

Eric

Hi Avater,

I'm marking the reply as answer as there has been no update for a couple of days.

If you come back to find it doesn't work for you, please reply to us and unmark the answer.

Best regards,

Eric

Hi,

I was out of the office for a couple of days so didn't reply.

Turning of the firewall on the MacBook didn't solve the problem. We did more searching and network sniffing on the mac side though.

Results are kinda unexpected.

Lync seems to work on Windows to Windows / Windows to Windows Phone. Even in different network or on 3G/4G.

The Mac to Mac and Mac to Windows doesn't seem to work with audio/video.

When we sniffed the MacBook we've noticed that during connecting a audio/video call it's trying to connect to the local ip (eg 192.168.0.x) of the other party. We can't figure out why it's trying that because a Windows client seems to work fine.

What can be the cause of this? Wrong edge config? I know that audio/video between two clients is peer-to-peer, so I can only assume the client thinks it looking for LAN connectivity instead of WAN. But why does a Windows client work? Any clue on this?

Hi Avater,

Please make sure these Mac clients do not use any proxy setting.

Best regards,

Eric