FWIW I received an external emitter from Sony last night. Have not tried it yet. They sent it no charge in response to my complaint about the buzz.
Unrelated note that might save some of you trouble: I found that this projector is not compatible with Monoprice's Redmere cables. These cables have an active component that improves the transmission signal. They rely on devices really conforming exactly to the HDMI spec. I think Sony got something wrong here because Redmere has really been careful with this standard but you never know. The PJ hangs unresponsive when you switch to an input with this cable on there. As soon as I pull the cable out it starts responding again. I tried two cables and neither worked with 4 different sources but those cables worked fine with another HDTV in my house.