Adjust Speak control's action to speak only once even if double clicked.

Adjust Speak control button action to speak only once even if double clicked. In electronics, this is called "debouncing" since pressing a physical momentary button actually bounces, sending several very short pulses to the control system, even though the user only felt a single "click" of the button. Debouncing interprets a short sequence of clicks as a single click, essentially ignoring subsequent clicks for a certain time period. Debouncing of the actual mouse button is handled by the operating system, so this use of the word "debounce" is meant to refer to the general idea of treating double, triple, quadruple, etc., clicks as a single click, until the Speak-ing is complete.
In some cases, users may not know if single or double clicking is appropriate, and in other cases disabled users' limited dexterity may make it hard for them to click only once, even when intended.
Since a Speak operation usually takes a few seconds, this feature could ignore clicks for a few seconds, or (more accurately) actually monitor when the speaking has finished, and then allow further clicks of the Speak control button. This should only prevent further clicks of the Speak control button from triggering speech - all other control buttons should operate normally, so that a user can prepare the next phrase while the current one is speaking/playing.
A more button-like appearance of the buttons would also signal the user that this is a single-click button, as opposed to a double click item such as a file or application.