What I would suggest is to use easily available Velcro sheet that has adhesive on the back that you can cut to shape- one half stick to the back of the device and the other half to stick to the wall. This is the type of product that is suitable:
What I would suggest is to use easily available Velcro sheet that has adhesive on the back that you can cut to shape- one half stick to the back of the device and the other half to stick to the wall. This is the type of product that is suitable: