iPod Video Volume Bug

Hello everybody

I have a problem with the volume for music videos.
if I play them and move the volume up to maximum then the volume is much lower, if I do the same with audio files. funny is, when is choose maximum volume and stop the video and play it again - the volume is much better. but if I touch the wheel, the volume will go down again.

hopefully this is a firmware/software bug. maybe it helps to reset the iPod, but I dont find a description for that.

(sorry for my bad english) thanks, tonic