Sonar 8 not getting Midi to VST

I'm new to the forum but am a proud Roland JV 1010 owner. I'm developing an editor and VST wrapper for JV family as a side-project and I'm having a problem with one of my client audience who uses Sonar 8. My simple test Vst - which just displays raw Midi from a DAW / Host - isn't receiving Midi data for him while it works fine for me in my Sonar X1 trial, VSTHost and FLStudio. He has updated to the newest available version of 8.3.xxxx and beyond that I'm stuck - I don't have access to his machine so I'm pretty much in the dark. I have googled a few issues where Sonar isn't passing Midi to a plugin but the fix usually seems CakeWalk Support remoting into a machine and pressing some secret buttons.
 
Is there anyone that can help me out, I'd really appreciate the input ?
 
AMC