Can't record audio from a VST in Sonar X3 Producer??

Hi all,
 
After 5+ years of use I think I may have discovered something Sonar is incapable of doing, but I really hope I'm wrong because if so I may need to switch to another DAW at least for my current project :(
 
I just purchased Studiomux/Audiomux which is a combination VST + iOS app that allows you to, in real-time, patch audio from certain iOS apps directly to a VST running in a DAW on a PC/Mac. (The iPhone connects via USB to do this with better latency than wifi/bluetooth).
 
I have this VST (audiomux) loaded up in Sonar, and I can hear audio perfectly on that track in real-time; I see the volume levels in Sonar for the Master Bus and the VST go up and down as I hear the audio flowing through, the source being a synth app on my iPhone.
 
HOWEVER... the VST itself, by design, does NOT react to MIDI in any way. Kind of like a microphone input... it's sort of it's own thing, and really has nothing to do with MIDI. In other words, it is designed to produce sound without any MIDI input from the DAW. The problem is that when I try to record to my VST track, it just records blank MIDI and no audio even though I hear my audio through Sonar during recording. Freezing the track does nothing since nothing got recorded to the track in the first place. I never see any wave forms after recording.
 
I've tried to create audio tracks and set the audiomux VST as an input to the audio track, but the audio track (with the waveform logo) in Sonar seems then to want to convert to a Keyboard/Midi looking track whenever I do that.... as if it is forcing me to record MIDI and not audio. I've tried playing with audio buses but I can't seem to route anything BACK from a bus to an audio track, for example, and I've tried messing with settings when inserting the VST and/or audio tracks but always get the same result.
 
How do I fix this, or can someone confirm this is a limitation of Sonar? Recording audio output from a VST irrespective of MIDI data? If so it's a shame, because the audio is flowing digitally over USB and sounds amazing in Sonar if I could only capture it somehow. (I realize that I could just run RCA cables from my iPhone, but that fully defeats the benefit of the 100% digital connection to the PC from the iPhone via USB.)
 
Otherwise Sonar has been an amazing tool, and learning it over the years has definitely been worth the effort.. I just hope there's something I can do to keep using it for my current project.
 
Any thoughts would be greatly appreciated.  Thank you!!!
-Natalie