I'm in the process of restoring a set of L300. I started a while ago and don't remember removing any damping material from them but I noticed a small bit (size of an almond) of that sort of material in the bottom of one cabinet. It doesn't look like any of the damping material that I've pulled from any cabinets recently either (though I will doublecheck). So, is there supposed to be damping material in the L300? If so, how much of what kind of material to use?TIA!