Backcheck noise

[Ron Nossaman]

> That's more like it.  Done all those things.  
> 
> David Love

Tape (or otherwise secure) a piece of thin leather over a 
noisy check, reset checking height, assess sound difference. 
Finally, replace one noisy leather, and assess. That ought to 
tell you either what it is, or what it isn't, depending on the 
results.

Starting to look like evil spirits.
Ron N