I'm trying to figure out why poor playback is happening. I have a 70s TV show (SD obviously) in MP4 format that have episodes that are all about 500MB. Every episode plays back with horrible stutters or dropped frames every 8-10 seconds. However, if I manually change the quality to Auto Convert it moves to 2.4Mbps and is dramatically better, though not perfect.

What might I be doing wrong here?