Sky q box causing problems

[Pdoffboy]

Hi. I'm currently getting very frustrated at my q box as it just constantly keeps rebooting itself.  I've tried switching it off and on again and taking the plug out, I've even done a factory reset and hard drive reset, but the problem still continues. I've previously had engineers out and they can't seem to find a fault. It also seems to be knocking the Internet out constantly as well. Can anyone suggest anything?