I am not familiar with any of your accessories but that is besides the point, for all intents and purposes they operate independently from a router. In your case you are losing your internet connection because the shub is rebooting and your accessories aren't causing this. I do believe this was a known issue with the earlier shub 3s but I thought it was resolved. You can try giving tech support a ring and tell them the shub is randomly rebooting, you are sick and tired of it and want a new one or you can setup a
thinkbroadband quality monitor to keep track of the disconnects over the next couple of weeks so you have got some hard evidence you can present of the problem.
If you want my honest opinion though, shubs are as cheap as chips and when you start attaching tonnes of other equipment to your network you are only asking for trouble. If you want to use all these other networking accessories the best thing you can do is buy a proper router to compliment them. Put the shub in modem mode, use a proper router and attach everything to the new router. It will work a treat.