Al, it sounds like you hit the nail on the head when you mentioned
your box is "heavy in lubricant."  If there is a contamination of
oil between the lead resonators, they are just going to make a weak
"plopping" sound instead of a nice crisp resonant ring.

The same applies for the dampers, contamination between damper and
tooth can quickly overdamp; in some cases it may even suppress the
tooth completely.

A simple, but careful cleaning may be in order.

Mark Singleton