HELP!! This is not a cheap machine. I've cleaned anything and everything out of it. It will work in reverse...most of the time. It will only work 'forward' on limited sections of the intake area...and that is hit or miss. Any suggestions? I'd like to take it apart to see if I can see what's going on, on top of the mechanism, but the lid doesn't lift easily and I'm afraid of breaking something. Please direct me. Thank you, Lisa Klingemann