This coffee maker started brewing VERY slowly recently... takes an hour for 10 cups!! It will be dripping slowly, then speed up, then stop for several cycles for an hour before the full pot is brewed. I've cleaned it thoroughly, opened the bottom, everything looks good. Could it just be old and tired? Anything I can do to speed up the brewing? I LOVE this machine, particularly the swing out filter basket and do not want to have to replace it. Thanks for any help you can offer.