Skipping while recording

I am using Audacity 2.0, installed from .exe file on Acer laptop running windows 7.

Using m-audio interface through USB, xlr connecting microphone to m-audio interface.

When I try to lay a guitar track while running the click track, bass and drums tracks, it skips, like a CD player scratching and it messes up the timing.

When I use the same setup to record the full band with no click or other track playing works perfect.

Wondering if there is a setting I am missing or if I need a better sound card or what.

Thanks in advance for any help.

Is there a USB hub in there somewhere?
Koz

No hub, right into the usb 2.0 on the side of the laptop.