ATEM TV Studio issue with viewing preview/program

On the ATEM TV Studio: probably something really obvious, but with 3.3 version update on Windows 7 system having an issue with the multi-HDMI out preview displaying the same source as the program, and therefore not being able to effect a cut or auto take between the 2 (except straight cuts between the 2 sources from the 'PROGRAM' mix panel that again display in both program and preview 'display windows' on the multi-HDMI out). Selecting any of the 'PREVIEW' source buttons has no effect at all on the source camera showing in the 'PREVIEW" window. Have tried resetting to default for the 'program follows preview' in setting the transition order.... running 2 x HD cams into inputs 3 and 4 via HD-SDI; all displaying onscreen correctly. I haven't experienced the issue before with the earlier software. Will try re-installing the software next, but audio and everything else is working perfectly. Any ideas most welcome.

quick update; on an uninstall/reinstall, the issue is resolved... so brilliant having the SDI audio recording capability now; and the ease of setting up a set level/left-right mix of all the separate channels...