Unwanted cropping

While it used to be much worse than it is now (before Connect would even accept an HD signal), I have noticed that Connect often crops 720p widescreen webcam images.  My preferences are set at the highest level, widescreen "HD" (fader bar all the way to the right).  I've noticed this with a 720 output from my tricaster (through a blackmagic webpresenter box) and most recently, through wirecast.  However, my laptop webcam seems to be unaffected - not cropped as far as I can tell.  In wirecast, reduced the canvas size to 1180x720 instead of 1280x720 before outputing to virtual cam and it seemed to eliminate most of the cropping. But I'm stumped as to why this is necessary. Any input would be appreciated.