I've have a problem with my jailbroken iPod Touch. When ever I go to play a video, like a movie or tv show, it just shows a black screen, goes unresponsive, and then resprings by itself in a minute or two. However, podcast videos still work, so I don't know whats going on. Any help would be appreciated.
Since you are on 4.1, I would assume you used the Limerain/GreenP0ison Jailbreak. You should include info like that whenever you ask for help, like device model and storage capacity, and installed Cydia Mods.
My iPod Touch 3G 32GB iOS4 Limerain JB'd plays videos fine, it's probably something you installed, or something went bad in during the JB.