Firstly, you must check that the video or audio file that you want to play supported by iPad or not. Now iPad just support .mov, .m4v, .mp4 and .mepg-4 files.
If the file supported by iPad, but can not be played, this file may be damaged. If the file is not supported by iPad, you should convert it to a format that supported by iPad. here i recommend Aimersoft video converter, or iPad video converter, which can convert almost all popular video formats for iPad.
If the file supported by iPad, but can not be played, this file may be damaged. If the file is not supported by iPad, you should convert it to a format that supported by iPad. here i recommend Aimersoft video converter, or iPad video converter, which can convert almost all popular video formats for iPad.