If you have an IGMP Proxy/Snooping setting in the router anywhere then turn it off. It's known to break Home Sharing on wireless devices for some reason. Some Wi-Fi Protected Setup options can also mess it up - if you have any turned on.

I think I've got it now!

I've added the MAC address of one iOS device to the routers 'Wireless Mac Filter List' even though Wireless Mac Filter is switched off!

As soon as I did this, Home Sharing popped up on my iPhone without any rebooting or logging out/in.

Confused why when its 'off' its blocking the wireless devices from passing through.

Also, although it can see the Home Share, it gets half way through loading it (takes about 25 seconds) and stops with an error message of 'Unable to load library'.

Also noticed that with the MAC address added to the list, the iOS device can connect to the router but can't access the Internet.

Will have to look this one up now...

Thanks to everyone for their help, but I've given up with this one now.

Asus support is nonexistent or nonsensical at best.

So, this router / modem will be going up for sale (1 month of use) and I've ordered an Apple AirPort Time Capsule router and DrayTek Vigorous 120 modem which I'm informed is totally compatible with UK ISP's and the Apple router (although its not cheap).

There will also be an OWC hard drive enclosure with or without a 2TB desktop drive fitted that was my Time Machine backup drive that is no longer needed.

Thanks again for all the advice, but I know when I'm beaten!

Not sure why you don't just let the router handle the DNS and DHCP?

 

I did use a Vigor 120 before moving to Infinity and it was a damn good modem. Good choice.

That's what I wanted: the router to do its job and leave the server to do its. But neither I not the Apple technician could get it working without significant work arounds.

Ironically, the cheap ISP modem/router that EE supply (but is locked to them) worked without issue!

The Vigor was recommended to me by someone more knowledgeable than myself, but reading about it, it seems to be very highly regarded and DrayTek say that it works with the Apple AirPort which is a big bonus for me at least.

Having tried to use various brands of router and network box to achieve a VPN into my (and client) Apple networks I now use a DrayTek Vigor 2830n and it just works. Whilst the protocols are supposed to be "standard" it seems some manufacturers have their own take on what this means so their products do not just work.

The only issue I have had with the DrayTek products is they can lock up and need a reboot every so often, but you can do this using telnet commands from any web browser.

The only other way around things is to set up a DMZ with an Apple server handling all the network traffic before it reaches your LAN. But this means buying more servers than you probably want to.

Asus router now gone.

Apple Tume Capsule router & DrayTek Vigor in its place.

No issues since an easy set up.

All my problems seem to be solved (well, most of them).