It is suggested that you convert the original or source video into low resolution. You can use different video conveter tool such as Total Video Converter, Xilisoft etc. to adjust the resolution into low format. 

Yes. To access the battery, the entire mp4 player has to be taken apart including the hard disk and PCB boards. This will void the warranty if any damage is made, ie customer will be liable for repair charges incurred. In addition, the battery used inside is not generally available. Unless you are a professional in this area or know what you are doing, it is best to sent it back to us if you need to buy a new battery. 

• Check your MP4 player's system requirements. Some MP4 players are only capable of working with certain operating systems and hardware, so refer to your player's documentation to ensure it is capable of functioning with your PC.

• Change the USB port your MP4 player is connected to if you have confirmed your PC can function with your MP4 player. Disconnect other USB devices, and try connecting your player to another USB port if you are still having problems.

• Try restarting your PC if it is capable of working with your MP4 player. Restarting your PC resets non-functioning USB ports, which may be your problem

• Try connecting your player to another PC to see if the new PC recognizes it. If it does, chances are your computer does not support the hardware necessary to run your player.

• Contact your player's manufacturer if you are still unable to get it to work with your PC. 

The software needed to convert the video into the correct format for your MP4 Player (e.g. AMV or AVI) is supplied with the product on a CD. If you have misplaced your CD, ask CD-R King technical Support and we will show you where to download the software for your MP4 Player.