I had a similar problem with VLC, and ended up just using
AutoHotkey to intercept the Play/Pause key when VLC is running and translate it to "send Space keypress to VLC".
Code:
DetectHiddenWindows on
SetTitleMatchMode 2
$Media_Play_Pause::
IfWinExist VLC media player
{
ControlSend, , {Space}, VLC media player
}
else IfWinNotExist foobar2000
{
Run foobar2000
WinWait foobar2000
WinActivate
}
else
{
Send {Media_Play_Pause}
}
return
That'll also launch foobar2000 if it's not running, since otherwise Windows insists on launching Windows Crapedia Player if no other media player is running. If you use WMP you can just remove the middle "else" block; if you use another media player just change "foobar2000" to the name of your media player.