Problems with Voice Comments

Has anyone had any experience adding voice comments to PDFs in Acrobat 8?

I recently began using the voice commenting feature in Acrobat 8 to comment on PDFs, however, I have experienced some significant problems. Some of the problems that I've enocountered include:

1. Very large file size produced by addition of audio comments (for example, on my Mac one 30 second voice recording created a 4155 KB audio file)
2. White noise/degraded audio quality (with and without a headset)
3. Audio drop out on occasion in recordings longer than 30 seconds

My PC seemed to turn out a much more compressed audio file (111KB for 30 seconds) but the quailty was not good, and in fact, much worse than on my Mac.

Does anyone have any recommendations for best practices using the audio commenting feature on PDFs in Acrobat 8?

Thanks,
Jessica