Note that this works on my computer with the iFrame Focus script activated. You can play around with it until you have it working for you.

To install this script:
- Download Autohotkey: http://www.autohotkey.com/
- Copy the below code and paste in Notepad, then save the file as LyricTheory.ahk
- Right click on the file and choose Open With... and then AutoHotKey

To use this script:
When the HIT loads, press 0 on your numpad. It will play the audio and choose Perfect. If the audio is perfect, press Enter and it will submit.
If the audio has a few wrong words, press + on your numpad and it will take you back up to "A Few Wrong Words" where you can edit the text. Then click submit.
If the audio is totally wrong, press - on your numpad and it will take you back up to "They're saying something completely different" where you can edit the text. Then click submit.

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#NoEnv ; Recommended for performance and compatibility with future AutoHotkey releases.
; #Warn ; Enable warnings to assist with detecting common errors.
SendMode Input ; Recommended for new scripts due to its superior speed and reliability.
SetWorkingDir %A_ScriptDir% ; Ensures a consistent starting directory.

SetBatchLines -1 ;Makes input instantaneous
SetKeyDelay -1 ; Makes input instantaneous

Numpad0:: ; perfect
Send {Tab 2}
Send {Space}
Send {Tab 5}
Send {Space}
Send {Tab 5}
return

NumpadAdd:: ; A Few Wrong Words
Send {rshift down}{tab 5}{rshift up}
Send {Down}
Send {Tab}
return

NumpadSub:: ; They're saying something completely different
Send {rshift down}{tab 5}{rshift up}
Send {Down 2}
Send {Tab}
return