My AV700 has the same fault. I found that it has something to do with the connection that the charger plugs into. If i biased the lead / connector over one way, the charge light would come on and start charging. However, there are times when the charge light does come on but it doesn't actually charge so it's a bit hit and miss. I'm looking for a repair job at the moment. Until then, i'll make do.
Shaved monkey, April 2009