I have no slightest idea. In all layouts I use (Russian, USA) space triggers play/pause in Rhythmbox. I suggest addressing further question to Rhythmbox developers. Both oss and latin9 define SPCE as space on first shift level. I suspect this is the issue with modifiers (Ctrl) handling in Rhythmbox (or GTK). But this is just my guess.
I have no slightest idea. In all layouts I use (Russian, USA) space triggers play/pause in Rhythmbox. I suggest addressing further question to Rhythmbox developers. Both oss and latin9 define SPCE as space on first shift level. I suspect this is the issue with modifiers (Ctrl) handling in Rhythmbox (or GTK). But this is just my guess.