I have the same issue here. My SB3 remains connected to the Wi-Fi but almost every hour it gets disconnected from the internet. The problem did not happen when the laptop was completely new, which was 10 days ago. But since it started 2 days ago, it keeps happening.
It seems to me that this is a software issue because as soon as I disconnect form and reconnect to my WIFI network, the internet connection returns. The whole process takes two seconds, but it is irritating to do this every hour.
Has anyone been able to find a solution except returning the laptop? I hate to think that I will have to reinstall all my software on another laptop.