Accept Burst Buton unavailable

I have a Sony VPH-1272 projector and I can't seem to get the USB-UIRT to learn the IR codes for the device. Some of the other postings indicate that possibly I should use the Accept Burst button to learn the codes. My problem is that the button is grayed out. I've uninstalled and reinstalled the latest version of Girder 3.3.4 and the USB-UIRT plugin. It is still not avalable. What am I overlooking?