Hi,
I m also having same problem.
With SL2_141 modem,Core2duo PC, Core2duo Notebook.
Problem found in Windows XP. in Vista no problem.
after using 10-15 minutes, browsing discontinued, but net status shows as connected.
I can disconnect and re connect Internet connection, but can't browse.
system sound also lost, It tells no active sound device.
Broadband Internet Status window, when opened, just flash and disappear.
IP address also not found at that time.
no use by modem restart, system log off, stand by etc, System restart needed.
Thanks in advance.