Proper placement of your Hub and mini blasters is important to make sure your devices respond to your remote. Harmony Ultimate can control your devices using infrared (IR) with the remote, the Hub, or the Hub and mini blasters. Infrared requires direct line of sight to the devices you're trying to control.
NOTE: The Harmony Ultimate remote communicates with the Hub using radio frequency (RF) commands, and doesn't require a direct line of sight to the Hub to work.
Here are some tips for the best placement of your Harmony Ultimate components:
Set your remote to control your TV, and use the Hub and mini blasters to control devices inside cabinets (see answer 360023254894 for help)
Place your Hub and mini blasters on different shelves where they're in line with the front of your entertainment devices.
Put the Hub on top of a device facing toward the front of the cabinet.
Set the mini blasters on the shelf in front of the device.
Bounce IR signals to devices off of the cabinet door and walls.
NOTE: Make sure your Hub and mini-blaster assignments are correct. By default, they'll be on for all devices. To customize your Hub assignments, see answer 360023254894.