[James Romeyn]

Shorting open audio inputs seems like a no-brainer; astounding improvements have been noticed. 

I recently decided there's nothing to loose by shorting open unused coaxial digital inputs.

Can unused optical inputs be shorted?  How?  Any affirmative reason to AVOID shorting them?  What's w/ the little plastic plug-thingy? 

TIA. 

[*Scotty*]

The little plastic plug-thingy keeps crap as well as light out of the optical receptacle. If you leave the plug in the receptacle it is inactive. 
Scotty

[Bob in St. Louis]

How would capping an optical input affect sound quality?   

Bob

[*Scotty*]

Bob,you got me on that one. I can't see any reason to cap off the unused SPDIF coaxial inputs or unused analogue inputs either.
 Scotty

[Speedskater]

Bob,you got me on that one. I can't see any reason to cap off the unused SPDIF coaxial inputs or unused analogue inputs either.
 Scotty

For the optical one's, it keeps the dust and dirt out.

[woodsyi]

You need to fill the Toslink slot with a black anodized aluminum plug coated with rare earth magnets which is specifically designed to suck up any and all loose photons in the optical chamber.  Even one loose photon could tunnel into the receiver chip in your DAC.  It will excite unwanted electrons and change all kinds of spin states.  The bottom line is that your jitter will increase exponentially.  Plug the hole.

This only affects digital sources.  Vinyl spinners can ignore any gaping optical holes.    

Peace,

[Bob in St. Louis]

All of the optical ports I've got have little hinged "windows" that keep the dirt out.
But are you saying I should be sticking that little cap in there if I'm not using the input??
Not sure what that would accomplish, unless I'm mis-understanding (which is entirely possible).

Rim, You're feeling a little fiesty aren't you?

Bob

[*Scotty*]

woodsyi,Now there's an explanation an audiophile can believe in.  Plug em if you've got em.
Scotty

[*Scotty*]

Bob, the purpose of the plug or the dog door is the keep crap,ie dirt and debris out of the receptacle,the hinged door is the more elegant solution.
Scotty

[Bob in St. Louis]

Ok good deal. Now I understand. I thought you fellas were talking about a sonic advantage by blocking the hole.
I gotcha now. 

Bob