[mikester]

So... the VPN is to your office I assume and the VOIP traffic is over that VPN via the DSL link.

My questions are these: Are you sure that this will fix your problem or will it just be added expense that doesn't. More research is needed to be sure before you spend the money. Plus - I still don't think a switch is your answer I think a proper router is as your problem isn't on the local subnet - it's the connection between the office and the home - namely the DSL link and your 4.5Mbit internet connection at work.

I think you need to set up some traffic monitoring to see how much bandwidth you're using at home becuase if the link is saturated then you'll need to address that before you lock things down with QOS. While QOS may make things better - if you haven't got enough bandwidth then spending this money isn't going to help.

Other questions - what is your router at the office, what is providing your VPN services (please dear god don't say windows). If you're using a Cisco Router at the office and it is also providing your VPN services it is possible that you could do the QOS at that point in your network (since when you are connected to the VPN essentially all your traffic will go to that device before it goes anywhere else) and thus not be required to do QOS at your home location and not have to spend any additional money.

I have a little experience with this (try something like 10 years now) so I would be happy to help.