Give me a day or so to do some research on it. I'll see what i can find out. The first thing i think of to be honest if you can is to completely format and reinstall windows. The second thing i thought of is did this always happen or just recently? If recently and you have system restore enabled, try doing a system restore to a date before this all started.

It could also be a problem with the actual modem causing things to crash, but i doubt it.
0warranty(most have 1-3 years depending). If it is I can give you the number to contact microsoft and they will troubleshoot/fix/help you fix the problem.