Have been having issues regarding audio popping on my new PC with an SB Audigy (old!), Via HD and a logitech G930. Anyway, after running http://www.thesycon.de/deu/latency_check.shtml (edit this http://www.resplendence.com/latencymon is better) for a minute you can easily see the peaks. They appeared to be random an no amount of disabling devices would help.
From here you can see the offending drivers. In my case it was the wifi and usbport.sys. Obviously, the usbport was anything that was plugged in to it, which then went into a hub full of devices. I switched a few devices around by moving them to different ports and updated all the drivers I could find. Seems to ahve resolved my popping issues at least.
I believe that PCI-e has a higher latency than PCI, so I’m assuming in the futre that this is just going to get worse, unless intel release a specific low-latency bus purely for things like audio.