Stops playing when I move cursor

[Jason622]

Everytime I move the cursor or try to shrink or expand a region, the audio stops playing for a about a half of a second. When moving or shrinking a region the audio stops when i first click on the region, starts playing again and will keep playing as I am moving or trimming the region but will then stop again when i release the region. Does anyone know why it does this? It does this on my laptop with XP installed but it does not do it on my desktop with XP installed. I can click anywhere I want on any region and playback never stops. On Vista however, it does it on my laptop and my desktop. Both systems are set to dual boot. I have a OWC Mercury On The Go external firewire hardrive. It is barely full and is brand new. I just transfered the files for a couple sessions on to it the other day and that is all that is on it. My laptop is a Dell Studio 1737 with 4 GB of ram and a Intel Core 2 Duo Processor at 2.63 Ghz and is also brand new. My desktop is Dell Inspiron with Intel Core 2 Duo at 2.83 Ghz and 4 GB of Ram. I am currently using Transit on my laptop and I also have a Fast Track Ultra 8R. This problem happens regardless of what M-Audio hardware I use. Any help would be greatly appreciated and thanks in advance. Oh, and by the way I have done all the optimizing tips on every operating system.