Below is a checklist that should help you to achieve good results:
a. Be sure to use only batteries each manufacturer recommend in the transmitters and receivers and be sure to change them regularly. Whenever
b. Always try to keep good line of sight between transmitters and aerials.
c. Be sure that the frequencies you are using are compatible with each other.
d. As much as possible avoid transmitters and receivers being placed near large metal obstructions especially mesh and girders.
e. Ensure the gain settings are set properly on the transmitters.
f.Try to maintain a distance of at least 3m between transmitter and receiver as too much signal can be as bad as too little.
g.When using multiple systems together, avoid any aerials touching each other.
h.Remember that the operating range will be reduced when in a room full of people as we all absorb radio signals.
i.By keeping receivers as high up as practically possible, stronger audio and longer range are more likely to be achieved.
j.To help in areas where high radio frequency is present and interference is occurring with your system, the squelch control on the receiver can be adjusted. Be careful not to set this too high as this could result in a drastic reduction in range.