I am running Ubuntu 10.10 within which I have a VirtualBox, on which I am running Windows7 Home Prem. Within the Home Prem I am running a 3CX IP PBX and bar an SMTP server so it can send voice mails via eMail, that is all. I have had this settup bar I used Vista Home Prem before, for about 2 or 3 years without any serious issues until the other day - when everything seemed to fall apart - but since then I am getting jitter on all calls. It is so bad it is totally inaudible. I have set up my router/LAN switch, a Draytek 2820 to use QoS as per settings on the 3CX Blog, but it makes no difference. Any ideas anyone?