It finally works!
But you need to use a Zoom 4506 Travel Router. First configure router with a browser. A little tricky because of the APN info required but Zooms website provide this for an iPhone. Next plug USB iPhone sync cable into router. Enable iPhone hotspot BUT as a USB connection and not WiFi. Wait for USB light to come on on router. Push on button Ts-480. Audio sounds fine with default settings but I may tweak it later. Previous poster is correct that iPhone tethered to a computer with ICS has too much latency. Now off to burn off some of my 4 gigs of data.
Disclaimer: This works for a non-jailbreak iPhone running iOS 4.3.4 with a legit data plan with tethering.
Regards
Tedd K6OI