How do I join a Lync/Skype for business online meeting without a microphone?

Question

The meeting is a presentation rather than a conference call and therefore no microphone is needed to provide feedback. Joining the call results in a Lync/Skype For Business error that there is no valid recording device and asks me to setup an audio device. There is an option to retry or to call a number but I want to listen through my computer using my headphones, not my phone.

I have read that this appears to be a bug that has been around since at least 2010 but does not seem to be addressed. Can anyone suggest a workaround?

Edit:

In response to suggestion that workaround might be OS specific...

Lync 2013 (15.0.4727.1001) / Skype for business 2015

Windows 7 64-bit

Answer 1

Method 1: You can use some virtual audio device, like this one. After installing it, you will see a new recording device in Control Panel (mmsys.cpl) and Lync will allow you to join the audio call.

Method 2: According to this article, you can trick Lync/S4B without installing any software but you still need admin rights to edit registry:

1. Insert your headphones into microphone plug for 10-15 seconds to initialize it (the microphone) in drivers.
2. Open regedit.exe and proceed to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\MMDevices\Audio\Capture.
3. Find the subkey with DeviceState = 0x00000008 and change it into 0x00000001.
4. Check for a new recording device using "control mmsys.cpl,,1", start Lync and join the audio call.

Method 3: If you don't have admin rights, just put some old headphones into the mic plug.