Do not position the units directly next to or under/above electrical equipment which blocks the transmission path. See picture.
Keep the virtual path to your receiver unit as clear as possible:
The fewer physical obstructions between the transmitter and the receiver, the more likely that you will be using the transmitters full signal strength, resulting in a clear picture.
Obstructions which can absorb, distort or block the radiation pattern are: ceilings, walls, furniture, etc.
Note: The human body is also an absorbent, distorting the radiation pattern.
Experiment: Try placing the device in several different promising locations for the best possible performance. Even a small change in position of the transmitter and/or receiving unit can make a big difference.