"charging is not supported with this accessory" and other problems with my ipod?

i have a 32 gb i think third generation ipod that is also jailbroken. Recently, when i plugged in my ipod for the night, it came up with the sign "charging is not supported with this accessory" sign and stopped charging it. i plugged it out and in and it seemed fine and was charged fully for the next day; However, this message has become more reoccurring and disrupts its charging no matter if it's plugged into the wall or into a computer because of this, my ipod died and is unable to significantly charge. itunes eventually recognized it but said it was "unable to connect to the iphone" because of some unknown error or some other ****. it just goes from one to the other. what is the problem and how do i fix it? thanks for reading all that and comment please if you can help :) thank you.