One of my colleagues has been investigating complaints of poor audio quality at a customer’s site this week. Lync’s QoE reports are blaming dropped packets, but the network team says they’re not seeing any packet loss – so what gives?

It would seem to be the Intel NIC driver that’s at fault – update the driver and BAM! the problem’s gone.

In this case it’s been on Dell machines, but we’ve previously encountered a similar problem on Lenovo ones.

Here’s a Lenovo KB calling it out:
Version 12.10.28.1801 Build 327525
(Fix) Fixed an issue where the computer might experience glitches in audio streaming during conference calls.

If you’re suffering poor audio, check if your NIC is running an Intel chipset and go hunting for driver updates…

With thanks to Ari Protheroe for the initial Tweet that brought this to my attention, and Tristan for his work nailing it on the Dells.
 
– G.