Using 24.5.1 on OpenBSD 5.9. OpenBSD's sndiod listens for XF86AudioLowerVolume and the rest, but if emacs is running in graphical mode with either GTK2 or GTK3 (I haven't tried lucid/AWT, but I will if somebody thinks that will make a difference) instead of sndiod receiving that keypress, emacs writes "<XF86AudioLowerVolume> is undefined" in the echo area and sndiod never receives the key, so if I want to change the volume I have to un-focus emacs (which can be problematic in a tiling wm). It works fine in terminal mode, presumably because the controlling terminal knows to ignore the event.
Is there a way to tell emacs to ignore certain keypresses when it has focus?