I was going to ask about the specs of your audio file, but then I got to thinking, why are you using AE for a video blog? After Effects is for creating shots or animated graphics; AE is not intended for doing editing.
You should edit in Premiere Pro. It is much easier to learn and much faster to work with as far as editing goes. Then, if you need to add some complicated graphics or visual effects, you can use AE for those few shots.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
No trees were harmed in the creation of this message, but several thousand electrons were mildly inconvenienced.
I'm using AE because I have it and am familiar with it. I use it to composite 3D animations that I render for my business. Since it's what I have, I'm using it to do video blogs as well. Don't have Premiere.