Software client or zero client? Using a Lync phone like the Polycom CX-300 or CX-600, USB headset, analog headset? Most of our Lync users have CX-300 phones but this simply won't scale for VDI. You consume massive bandwidth handling the USB traffic then kill the CPU on the backend having to handle USB to audio decoding. For this reason, we are using purely CX-600s for VDI users with Teradici zero clients. Yes, the phones are a little more expensive but the audio quality is WAY better and it's better for the network. You can do QoS this way where you couldn't with USB phones.
Unfortunately, the Lync client treats the CX-600 as a USB speaker if you try to do a Lync video call and there's just not enough USB bandwidth in the zero client to handle the USB camera and the USB speaker. We've talked with Microsoft about this saying we want the audio to go out the analog speakers we have connect to the zero client rather than the CX-600 and they responded that this is one of several things that's being re-written in the next version of Lync.
