Excessive registry activity by svchost, WWanAPI error

Question

I am using mobile broadband connection. I am restarting it often via task scheduler. After a while the machine experiences slow downs, high disk usage, high CPU temperature. ProcMon investigation showed that Explorer.exe and svchost.exe are excessively accessing the registry. When I've killed the Explorer, svchosts was still reading the registry and machine did not change its behavior. The svchost is connected with Internet Connection Sharing which is enabled on the mbn interface. Also, the Explorer was excessively reading WWanAPI.dll which is part of mbn subsystem.

Well, I've apparently tracked the whole thing down and this might help others, however:

• why is an mbn failure causing excessive registry usage,
• the mbn interface can still work with no serious problems for many hours (it then does fail however),
• restarting ICS did not help; what should be restarted to fix the issue without reboot?

I can use the hardware switch and it does help, but it is very problematic.