Do you mean that you have applied a fast motion effect to your Timeline video? By what method?
When you apply fast or slow motion to a video clip that has audio linked to it, the audio will be distorted if you are using Time Stretch to create the fast or slow motion video effect. You can gain some control over the level of audio distortion by checking "Maintain Audio Pitch" in the Time Stretch dialog. But that option will get you only so far with regard to the level of audio distorsion in these cases. Please take a look at my blog post titled "Time Stretch - Fast Motion Without Degradation or Distorted Audio"
If you are using Time Remapping, the Time Remapping feature's workspace does not accept audio, only the video part of the file to which you apply your motion effects.
Please give more details on what you are doing, and then we can discuss this further.
This seems to be exactly the same issue you brought up in another thread.
If so, please don't double-post the same question more than once. it's very confusing.
As you have two posts on the same issue, I have copied ATR's Reply #1 from this post, to the other thread (http://forums.adobe.com/thread/1407550?tstart=0). Here, his Reply was #1, but it now is down the other thread. I Copied/Pasted it there, to help consolidate the two threads.
This thread will be locked. Please continue all troubleshooting in the other one.