Lync 2013 has made it even harder than before to transfer a call.
Now it takes a hover and 2 clicks before you can key the party you want to transfer the call to.
If the user mistakenly clicks instead of hovering on the "handset/mike" icon, they end up accidentally muting themself - presumably at a time that they're still talking to the caller whilst trying to make this complicated transfer process appear seamless.
For bonus points, improve this (removing the hover?) at the same time as adding announced transfers...