Why don't you try this as a script. It worked testing on my computer and opened the File menu. Notice I have a few commented out lines with a semicolon in front which will be ignored when running. I left them in so you could use them to troubleshoot if this doesn't work. If you don't need them, I'd delete them in your final version. If it still doesn't work remove the semi colons on the MouseGetPos & Msgbox lines and it should display your mouse coordinates before and after. Let me know if you have more problems.
#SingleInstance force
SetTitleMatchMode, 2
CoordMode, Mouse, Window
;To comment out any lines use a semicolon in front like this line
;#If WinActive("ahk_exe i)SONARPLT.exe") ;scook's version doesn't work for me
;#IfWinActive ahk_class SONAR Platinum Platinum
#IfWinActive SONAR Platinum
a::
;MouseGetPos, OutputVarX, OutputVarY
;Msgbox, Before`nOutputVarX: %OutputVarX%`nOutputVarY: %OutputVarY%
Click,40,33
;MouseGetPos, OutputVarX, OutputVarY
;Msgbox, After`nOutputVarX: %OutputVarX%`nOutputVarY: %OutputVarY%
return