A story of Audio Problems installing with XP Pro SP2 CD (Happy Ending)

I've been trying to think of somewhere to log some of the issues I've had with my systems in case anyone else experiences the same things. Googling seems to bring up my previous posts so this seems as good a place as any.

The problem:

Clicks, pops and general; quality problems with audio played from Windows Media Player, Winamp v2.81 and Winamp v5. No problem with on-board audio but problem occurs when using an M-audio Transit USB device.

Using a fresh installation of Windows XP Pro SP2 on two different laptops I experienced the same problem (much worse on the Compaq laptop than the Toshiba). I tried the supplied driver CD and the two different drivers from the M-Audio website. The problem was much worse using Winamp than Windows Media Player. I followed all the advice on the M-Audio web site including switching off speedstep and all other power management options. No improvement.

Resolution:

Instead of using an XP Pro SP2 installation I reverted back to an old drive image which was a clean install of XP Pro from a non-sp2 disc with SP1 and SP2 manually applied after the initial installation. This fixed the problem on the Toshiba.

I have installed the basic XP Pro (without any service packs) onto the compaq and although I have yet to apply SP1 and SP2 I'm not currently experiencing the issue.