Hi Venkat.
In this situation, there is no need to use wfview for audio directly as you already have the USB audio input/output ports provided by the rig. If you are using digital modes, simply connect your software to these audio devices. You can ‘listen’ to the audio coming from the rig by setting the ‘listen to this device’ option within the Windows control panel.
The main downside with connecting to the 9700 over USB is that the waterfall is significantly slower than the one provided over LAN though.
73 Phil M0VSE