Nice another M-Audio fan.
I myself actually use the Delta 1010LT and I've been thouroughly happy with it's performance. I'm pretty certain that the sound card is not the issue unless it's physically defective, but we won't jump to that conclusion yet.
I'm inclined to wonder what type of maintenance regimen you have iwith your machine. Do you run regular defrags and whatnot.
Also, and it's been a while since I've installed sound drivers, but I seem to recall having to remove drivers before installing new ones, you might want to try that. Check your device manager for resource conflicts and If your machine has onboard sound, disable that.
I'm not sure what the audiophiles control panel looks like, but I'm hoping there is a section where you can adjust sample rate for recording and playback. I'm not sure what you mean by "slow" if you mean that it's like playing a 45 RPM record on 33 RPM setting low then you may want to adjust your playback sample rate to 44100 Khz. If you mean choppy or stuttering, there are quite the variety of issues possible from faulty
ram to a hard drive not being able to keep up with read/write requests to driver issues.
If none of the above suggestions work, consider running through the instructions in the ///Prework\\\ Link in my signature and post the resulting logs (*** attached text files please) and we can do a rather thorough malware check. A chkdisk and a defrag may not go amiss either.
I must say that I appreciate your taste in sound hardware.
Last but not least, a warm welcome to the forums.