Anybody own a component that sounds better with the cover off?


I'm not a big tweaker at all but recently I've been figuring out a problem I've have with my Lamm LP2 and now that it's fixed I've been listening with the cover off and then on and then off again and it just sounds better with it off. Things just seem tighter sounding. More precise. 

I've gone back and forth so I don't think I'm imagining it. It's not like I'm putting crystal on top of the speakers or anything :)
dhcod
Audio Research has experimented and changed their top and bottom plates for their non amp components a number of times moving from metal grates to the smoked plastic because they sound better.
Yes; the Eastern Electric Minimax DACs that I have sound better with the covers off, because I have rolled into them discrete opamps. 


TT cover on/off———no difference. 

Change cartridge, ...adjust weight..... cover off/on - cartridges sound same with cover on or off,
I leave them on for convenience, and to keep in good shape, when things come off, get stored, scratches, cracks magically appear (PFM)