Lose audio every few minutes in recording

When I record a 30 minute podcast, I get about 3 or 4 points where I lose a piece of what I was saying and it so that it sounds like I am muted and lose a second of audio.  I am not sure I think it may be memory or something cause whenever I play things back in post, I get artifacts of what I just said. and I lose sound quality.

What are some ways to make Audition more efficient?

I have:
Athlon 2000+
512 memory
2 soundcards

Love to hear suggestions.  Thanks.

Luke