..further update - Downgraded... OK so after testing and testing some more I downgraded the Audio 8 driver to no improvement. I downgraded to TS v1.1.1 - no cracks or pops but still whilst TS is running I get the CPU spiking to 53% then it drops off - it's like a continuous waveform. Peeking at the sytem monitor as it soes this shows that TS is the app causing the spike - windows doesnt do this when TS is closed. Is this a "feature" of TS? Absolutely everything that can be disabled (acpi - even as far as the DVD drive) are disabled. I cant strip Vista back any further... And what's this DPC that everyone keeps mentioning BTW? - where can I find it?