I'm not exactly sure what you mean by gaps. Is this silence? A 4 year old computer may strain when making a recording. Lots of things factor into this such as available memory and disk defragmentation.

A few thing to try not knowing your situation:

. Defrag your drive
. Turn off background programs such as virus and spyware monitors
. If you are using RealTracks, turn off fast generation

If you still have the problem, post more info such as your computer configuration, the method you use to record, and some info about your song (RealTracks, etc).

Rachael