asterisk users - Jun 2004 - FireFly - no sound after first call

I've been watching to see if this problem comes up with anyone elses
firefly - but so far i'm the only one experiencing the problem.

When I connect to either my asterisk server or FWD all goes well on the
first call.  I can hear and talk.  But every call after the first one I
end up with no sound - not even ringing.

I use win98 and have tried it on two systems with win98 installed.

thanks
joe

p.s. if any other info can provide let me know.