skipping skippin skipping
 

ok .....
i have done the defragmenting the system file check and scan disk i have also.....got a new sound card nothening is helping now it was fine until they installed my cable modem....why is this happening..

Obviously this isn't a real solution but try unplugging your cable modem and see if the modem itself is a problem or something that happened to come along with it when the modem was installed.