It doesn't basically seem to like a lot of connections.. (cheap hardware never does)..
It's not the hardware, it's the software running on it.
Even the cheapest router hardware these days is powerful enough to do most everything a household needs, but so many manufacturers ship their devices with shoddy firmware and never bother to fix things.
That's why i'd never buy something that couldn't be flashed with an open-source firmware like OpenWrt
. OpenWrt can enable even a £50 router to give a £500 Cisco a good run for its money. I recently wrote a blog post
about some of the things i'm doing with OpenWrt. It's an extremely flexible enterprise-grade router OS.
I don't know why Zen would ship these poor quality modem/routers out. Supplying the OpenReach modem (which are pretty competent at their jobs) along with a £20 router flashed with OpenWrt would provide a much better solution.