I can't seem to make any sense out of the GL2 instruction book for setting the custom key to sound attenuation. The "button" always seems to be set to the default setting which is "index write". Can anyone explain how to get the custom key setting to change in "camera mode"?

Hi Barrie,

According to page 58 of the GL2 operator's manual, it should be a fairly straightforward matter of:

Menu > Custom Key > Select function > Close menu.

Does that work for you?