Video speeds up when changing audio

When playing a video and I change from AAC to Dolby Digital, the video speeds up. The audio stays the same speed, but the video speeds up and is not synched up.

I’m guessing this is in an MP4 / M4V file?

If so, go “Vote” for this issue:

(Yes, I understand that that issue is in the SMP forum, but the exact same issue affects both boxes the same way.)