I've been using a Zyxel VMG8924-B10A for 4 years, ever since VDSL finally became available at our exchange. It's been super reliable, apart from a really annoying bug which has been present since the beginning and numerous firmware updates have failed to fix:
Periodically it refuses to assign DHCP IP addresses to one or more devices connected to the LAN.
Other devices connected to the network will work fine, but for some reason the router will randomly refuse to assign a network address to some devices. This happens even if the outer has been set to always assign the same IP address to that device. And any device on the network can be affected - computers, TVs & video recorders etc. But devices which have an IP address set manually and don't rely on DHCP are never affected.
Rebooting the router resolves the problem, but I would desperately like to try and find a solution. (It has become so annoying that I am reluctantly looking at having to replace this router.)
The network is a small home network with the usual assortment of computers, TVs etc. connected. I don't use the wireless networking on the router, everything is connected via Ethernet cable. (A separate wifi access point is used as & when required if a phone or tablet needs to connect to the network, but most of the time wifi is not used in the house at all.)
The problem can affect any device on the network (unless it has been assigned an IP address manually, as a workaround).
I tried contacting Zyxel support after I first got this router and discovered the problem. They asked me to capture the network traffic with Wireshark so they could analyse. But lost interest after I pointed out that the problem occurs at random and I have no way of making it malfunction, so I would likely have to leave Wireshark running for a couple of weeks. I hoped a firmware update would fix it, but the problem is as bad as ever. (I'm currently using firmware 1.00(AAKL.28)C0.)
Has anyone else experienced this problem, or have any ideas how to fix it? (I live in the UK.)