Maybe your BASE TV remote control is no longer paired to your BASE TV box.
Your BASE remote is no longer paired to your TV or sound system. Try to re-pair them.
Still not solved? Then your TV or sound system is not compatible with the BASE TV box. Use the remote control of your TV or sound system to adjust the volume.
Still not solved? Then your TV or sound system is not compatible with the BASE TV box. Use the remote control of your TV or sound system to adjust the volume.