Nether portal traveling "whoosh" sound plays every time a player simply walks across a portal

The bug

If the player walks into a nether portal and them quickly steps out, the "whoosh" sound played when traveling to the dimension gets needlessly played.

How to reproduce

1. Build and light a large nether portal
2. Step quickly in and out of the nether portal (to either side), in rapid succession
3. Wait, and listen to the "whooshes" you hear. They occur as many times as you entered the portal.
4. Compare to the whoosh heard when traveling to the Nether in the normal fashion.

Proposition: The extra sound should be cancelled or changed if the player leaves the portal prematurely.