If you have an onboard audio chip, then make sure to set the hardware acceleration to 3/4 from Full. Onboard audio chips do not have any (or mcuh at all) hardware support for playing audio.
The 'hardware acceleration; slider just set sh priority for playing sounds.
Akso note, if you have custome sound loaded and are using onboard audio chips you will again experience potential performance issues as virtually all custom sounds are sampled at a much higher rate and are simply larger files requiring more time to load and play.
If you are using a USB headset, then it is going to be difficult to keep it from pausing at times. USB headsets require the most CPU time to do anything with audio as comapred to even the worst onboard audio chip.
Bootomline: It is a resource issue of some type.
