It seems that nowadays if you have WMP10 on your desktop and anything but WMP10 on the device you are transferring to the results will be flaky at best. To rub salt into that wound you can't download a version of WMP10 to your 1940 Ipaq.
...It seems the best way around this is to steal your music and use a 3rd party player.....just kidding...sort of.

I think my statement is a bit of a testament as to how frustating DRM is becoming for those of us trying to do things legally.
When I was using my PDA2k which is sans WMP10 I got so frustrated I simply gave up trying. The results trying to transfer music to it and get consistent results was impossible. Now that I have a JAM with WMP10 things are much better.
Dave