HTPC underwent a CPU & mem upgrade, went from XP Pro to 7 Ultimate 64bit Fighting for 2 days with sound issues in many players, most prominent in streaming flash content like Youtube (less problematic, still annoying in Winamp, Foobar, WMP) NO issues with even fullHD stuff in VNC. System: Ram: 3GB MoBo: Aopen i945GTm-VHL (socket 479) CPU: T7200 GPU: HD2600XT (iSilence) Soundcard: USB DAC (works with standard Windows USB Audio drivers, nothing to update) NIC: USB WiFi with Atheros chip Testing drivers and components, I am pretty sure the problem is most prominent (unbearable), whenever I have the graphics card installed with proper drivers! Tried several driver versions under 7, and even gave Ubuntu 64bit a quick try, same there. I have yet to try another graphics card in there. Temp fix now is an old PCI USB card I dug up. Installed the card and plugged in the USB DAC only. Works to a point where I can live with it for a while. I am still very interested in hints, suggestions and advice on how to solve this! PS: Hello Forum and thank you already for all the past contributions made about this problem. It helped allot in exploring possible causes and excluding others.