Sandisk Clip Sport audiobook problem

3300- 600 MB per book? In how many files? What format and bitrate? For spoken word podcasts, I convert them to 32kbps mp3 mono right after I download them to save space. Using a low bitrate also increases battery life. If a speaker is moving while he is talking, listening to it in stereo can give a dizzying feeling. The Clip Sport has a less capable processor than the Clip+, although its power usage is only around 45% of that of the Clip+. The Clip Sport might have trouble with very large files in certain formats.