You need to RAM preview to get a smooth playback while in AE. Standard preview will render frames and play cached frames as fast as it can, without audio or any guarantee for real time playback.
RAM preview mixes your audio, renders your comp (according to the current and RAM preview settings), saves the frames in RAM, and plays them back in real time. It’s limited by the amount of RAM you have available.
FAQ: Why is my output file huge, and why doesn’t it play back smoothly in a media player?
Hopefully the links above explained why it’s not playing back smoothly. As to what you can do to make it better, it depends…what is your deliverable, if it’s just for yourself, you would want to find a codec with a bitrate that your computer handle and that looks good. On my machine .wmv’s and h.264 work really well, but you are on a MAC and I don’t know what plays well on those machines.
If you are delivering it for someone else, you want to give them the highest quality possible and just learn to live with the fact that the highest quality generally won’t playback well on PC.
Johnny Cuevas, Editor
Thinkck.com
“I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”
—THOMAS EDISON on inventing the light bulb.