I use a headset and at first all was fine but now my voice keeps breaking up making a conversation impossible. It's not my mike and I've contacted Skype 3 times - they were quite helpful but although I've configured everything correctly still no way. What have I missed? I want to buy a VOIP USB phone but wonder if I'll have the same problem with that. Any ideas please?

Might be your connection speed!? You can test if it's your connection speed by trying to have conversations on MSN, Roger Wilko, or other similar programs. If they don't work either - it's not a Skype problem.