Hum, this looks like an interpretation problem of your AVCHD file.
Short answer: AE struggles to read correctly your file.
Long answer: AVCHD has ton of flavors and revisions based on the original recorder device (camera), and the recording mode (preset you choose). AE supports most of those flavors, but new ones are released everyday on the market, making it difficult to be a reliable format. If you have not yet updated to 9.0.2, I recommand updating now as your AVCHD flavor support might be included in the update.
If it dones't change anything, I recommand you converting your file to a lossless codec format (like QT animation) to manipulate it correctly inside AE.
You can try the free converting tool MPEG Streemclip.
Hope that helps
Ahh... and to think CS4 would be the solution to all my AVCHD edits... Getting the update will take awhile for me, will update you when I finish. Thanks.
Unfortunately, the update did not solve the problem. I guess I will have to convert the file. Thanks for helping.