Amazingly, worked for me as well! i had to remove the battery before I hit it (not as hard as you might think, more like a firm tap on the speaker) and it seems to kick it back into action, at least for a while. Saved me a hundred pound repair fee, so thanks.

I too couldn't believe it. I haven't used my camera for months and read this today and it actually worked. I am a video producer for a professional sports team and truly am not an advocate of "whacking" gear that doesn't work. However, the advice of smacking the GR-DVL805 with the battery removed after an E04 warning truly worked. I am dumfounded. Thanks folks for the solution.