BigBox button overrides Steam game button

[mrl72]

On my control panel I have a dedicated button "Exit". In BigBox this is mapped to "close active window". In Mame games this works fine, it closes out Mame and returns me to BigBox, but in Steam games it does the same but leaves the Steam game running in the background. In Steam I have the button mapped to something else. Basically, BigBox is overriding the Steam controller mapping. Anyone know how to fix this?

Edited January 6, 2020 by mrl72