I had Win 7 issues and could not get rid of the crackles at all (using USB sound), I reverted back to all sorts of version but nothing.
Decided to post just in case this helps someone else:
Win 7 says its using Virus TI Audio 2.8.45 in device manager but its all lies, its still using the dreaded 2.9 which is nasty.
First uninstall everything from access
put this line into your environment variables in windows 7 , DEVMGR_SHOW_NONPRESENT_DEVICES , set it to 1 (restart)
now open device manager and select show hidden devices from the view menu, remove everything Virus related (I had some under sound, video etc... and other devices)
bounce the system (restart)
now install the older version (not 5) and plug in the virus, watch the install when you plug it in, make sure windows doesn't say 2.9 when its installing the driver or you may have to remove the vi files from system32 as well.
thats it and it now works, it looks like its the 2.9 driver thats the issue, I am on 64bit and it has to thunk to rtas but still, its still just plain naff
access - please spend some money and phone MS asking them how to uninstall all files from your uninstall routine, if this had removed everything then it could have saved me days....