tj.pauseSound() stops a sound, but keeps its current position. If you call tj.playSound() again, it will play from where it was paused.
If the sound is already not playing when you call tj.pauseSound(), the call has no effect.
The following demo shows loading a sound and then playing it on a button click. And provides a Pause button for you to pause it half way through. When you click Play again, it will play from where you paused it.
If you'd like to Stop a sound instead, e.g. stop it and set its position to zero, you can use tj.stopSound().
If you'd like to see a demonstration of a range of TinksJS Audio functions, you may like to check out the Audio Player example.