I'm new to computers and have a Packard Bell with Windows XP. Recently it has started to speed up after beening idle for a while. It is ok at first, but if I leave it switched on and don't use it for a few minutes then it will play CDs and the radio at very high speed, and it will also dial up the internet and play sounds very fast. I've restored it to an earlier date but that has not put things right. Can anyone advize me to what I have to do to correct it?