Active Sync Problems after Installing Broadband

Since installing Braodband (external USB modem), my Ipaq
will not synchronise with my desktop.
Ipaq is placed in Cradle.
Active sync starts, and Ipaq is seen to be "connected"
for 2 seconds
Ipaq is then disconnected
Ipaq then automatically tries to dial the internet (via
infra red port)

I have:
Upgraded to Active sync 3.7.1
Re-booted desktop
Soft re-booted ipaq
Run the "connection wizard" (This cannot find the Ipaq)
Eventually get message on Ipaq "Cannot start
communications with the desktop computer. Winsock
services could not start due to critical error (Error %d)

I have no problem connecting to my laptop (I have
parnerships between the Ipaq and both laptop and desktop)
Any ideas???