The sound in a video clip will change on it's own.
Sometimes you can close the program and restart to fix, but I'm unsure if saving before closing is a good idea, (kinda locks in the glitch and it would be a pain to sift thru auto-saves to find when the glitch occurred) and sometimes Power Director won't even restart requiring a reboot, which means closing all other work in all other programs and restarting and reloading them.
I think this is good product for the Novice/Low-end user, but even a beginner will outgrow it quickly.
(Oh, and BTW, using colors in the verification code makes it nearly impossible for people who are colorblind. 1 in 12 men and 1 in 200 women.)