If the broadband (VM) connection is OK for wired devices and those on 5 GHz, then the problem is the 2.4 GHz wireless, and if it persists with your own mesh, then it isn't anything to do with VM. Changing to Sky won't help in that case.
What sort of property is this?
Have you checked for overlapping 2.4 GHz networks?
You don't have baby monitors, or a microwave over (in particular Panansonic)?
You're sure that the broad band latency, speed and reliability are A1 on a wired connection? Both wired and 5GHz handle brief disconnects much better than the sort of dumb-as-a-cabinet-minister devices that are limited to 2.4 GHz, and anything pertaining to be "smart" is assuredly the complete opposite.
I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more
Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks