When my wife decided she wanted a cat, I bought a couple plastic lenses designed to be used on a 4 ft. fluorescent light fixture. They are translucent and pretty thin, maybe 1/32 inch, strong but very flexible. When I'm not listening, I bend them around the front of my speakers and secure them with a bungee cord a half foot up from the floor. They are easily removed for listening and fully protect the grills from the cat when the system is off. Aesthetically pleasing? Well, no. Effective? 100%.
Otherwise, try the "velcro babysitter"...a square of velcro a couple square feet. One side mounted about half way up the wall of your choice, the other sheet with a hole cut into it large enough to go over the baby's head and secured around the baby's torso. When you're not in the room, you just velcro the tot to the wall.
Otherwise, try the "velcro babysitter"...a square of velcro a couple square feet. One side mounted about half way up the wall of your choice, the other sheet with a hole cut into it large enough to go over the baby's head and secured around the baby's torso. When you're not in the room, you just velcro the tot to the wall.