Unable to fix missing mail sound on Mac Pro 2010

two possibilities are:

• You literally JUST lost the sound. Maybe it will come back after a Restart.

• you lost your connection to your outgoing mail Server, and you will see an "OutBox" appear, and your unsent emails piling up there. In that case, use

Mail > Window > Connection doctor ...

...to check the status of all your email servers. If you Get a Red light, click on it and check the settings and other issues.

Nope. and Nope. Just disappeared. Speakers are working fine for everything else. Does this have anything to do with the "pause" of mail I was able to set? But it's been set for months. Poof. No whoosh.

<< the "pause" of mail I was able to set? >>

I don't know what that is. can you elaborate?

Sorry. The "Undo Send." Apparently the speakers are acting up. I think there may be a short. Had to wiggle the wires and then rebooted. Sound back. Thanks for the response.