Help with iRiver H340 (MP4)

[RowanSpry]

Two problems at the moment..

Firstly, it keeps turning itself off. Even when its full charged, it turns it self off after 20 minutes. But if im pressing buttons alot, then itll do it sooner. Maybe in 2 or 3. Ill try turning it back on again, but itll just SQUEEL for a little while, and then turn itself off, so it wont start for another 20 minutes or so. The only way to make it stop this, is to have it constantly on charge. Its the only way to stop it. My dad said something about the battery, i forget the name of it...But its a li-polymer battery. He said if i kept it on charge too much, then it 'forgets' what its full capacity is or something. he advised me to run it flat alot, and then charge it up etc. but this hasnt been working. Do you think its the battery? Shall i replace that battery? (li-polymer, 3.7v) As i never kept it on charge very long. Though it was second hand, and we DID replace the hard drive once, after it broke because i dropped it.

Secondly, its an MP4. I bought it second hand, with the video player upgrade. And it worked great, i could put videos on there and they would play. but i THINK since replacing the hard drive it was, that it hasnt played videos anymore. Its still got the option to view them when i set it to video play mode, but it wont see the videos (thus not playing them) no matter what format. Do i need to reinstall any kind of firmware or anything? Or am i doing something wrong.

Thanks