If you can't make your Virus TI to work perfectly using Virus plugin integration , let me tell you my tricks and my explanations to understand all Virus TI INS and OUTS of MIDI&AUDIO signals .
I have discovered that is just impossible to use Virus TI VST integration in multimode using USB Virus outputs because of sync timing problems especially when it comes to recording Virus ARPs or when I'm using different VST instruments side by side with Virus..
For me Virus Ti & VST Virus plugin integration are working together perfectly ,only if I'm using Virus analog outs and not USB outs and if I use Virus as a main soundcard for all my Virus TI work, so basically in this situation I can't bounce the audio signal from Virus to DAW, so i must use onother soundcard in WDM mode to capture and record the Virus TI audio signal in Sonar.
So the Virus TI audio signal is captured by another secondary soundcard and is recorded directly in Sonar .The signal is not recorded directly from the Virus to Sonar. Also Virus is used as the main soundcard. The other soundcard is only secondary used to capture different audio signals like microphone, Virus Ti signal..etc. For this reason I normally disable the audio outs from the secondary souncard and I keep only the necessary inputs . For secondary soundcard i use ECHO Audio Fire 8 with FIREWIRE connection.So for this reason, Virus Ti outputs are connected to my monitor speakers . And Virus Ti digital outputs are connected to my secondary soundcard. Because I work with Virus the other soundcard is left with no monitor speaker connection and is used only for incoming audio signal..
To be more clear , when Virus Ti plugin is using Out1 L&R , this means the USB cable will use only MIDI data Virus >PC and DAW audio data that comes from PC to> Virus when your project is playing.
In the opposite scenario , if you select USB outputs from the Virus plugin , Virus must send the audio singnal from the Virus > to > Computer and from Computer > back to > Virus . This means 2 steps !! not just one !! so this means a big time loose, and means that the USB cable and Virus processors will become exhausted, because of to much information. So basically in this situation Virus will sound desinchronized from the rest of your VSTs because he's loosing time. You will think that something is wrong with Virus TI..but in fact something is wrong with your setup because Virus is loosing time.
To be more clear if you sellect Out1 L&R from your Virus Plugin, and if you're using your Virus soundcard in the main role, you have the fallowing signals:
1) Your VSTs & audio tracks (your project) sound that comes from PC > to Virus TI > to speakers
2) Your Virus TI sound that comes from Virus TI > to speakers
3) MIDI data from Virus TI > to your DAW
Because of WDM mode i can use 2 soundcards.The other soundcard is used for microphone recordings.... Pretty complicated but once you understand is simple and is working perfectly .This is the trick to make your Virus working perfectly in case you have big timing problems using the Virus plugin integration. Keep in mind that with ASIO you can't use 2 soundcards at the same time .
And DON'T FORGHET TO PRESS THE LIVE BUTTON INSIDE YOUR Virus integration plugin. 
Also you must set your DAW latency to 128 samples-2,7 ms
Also you must update your Virus and your Daw with the latest updates
Also don't forget to check your PC system using a software called DPC latency checker because you must have your system latency bellow 80 us so if you dont have that latency you must set you sistem . And this means to disable different Bios and CPU functions ....Took me 2 weeks to find all settings .I will upload some special tutorials soon regarding how to set DPC !!.
Also you must turn off your USB port's power save option. In Windows XP Pro
- In Windows, click on Start >Control Panel (or Start >Settings >Control Panel).
- Double-click on System, then open the Hardware tab.
- Click Device Manager.
- Click the + at Universal Serial Bus Controllers.
- Right-click USB Root Hub and select Properties.
- Open the Power Management tab.
- Clear the checkmark from Allow the computer to turn off this device to save power.
- Click OK.
- Repeat this procedure for the USB 2.0 Hub.
For example is not working if I use ASIO because with ASIO I can use only one soundcard .
WDM seems a lot more flexible to set 2 or 3 soundcards for my project. I normally use the secondary soundcard only when I need to record audio inside Sonar. Maybe my setup looks a litle strange but is working . I can't find another way to work with Ti perfectly. Now I'm happy with my setup and I don;t care if is a little difficult because I like the perfect results.
If you find my tutorial extremely useful and helpful and you manage to setup your Virus perfectly ,also I give you 50 sounds for free and in exchange you can consider my cheap soundset for purchase >
http://www.youtube.com/watch?v=PP0V0zeI1RI