Check to make sure both the channel and the privacy code match on the transmitting radio and receiving radio(s). If one radio can receive a transmission but the other can not the most likely cause is a mismatch of a privacy code. Check the volume level of the receiving radio(s). If an accessory headset or speaker/mic is used ensure that it is fully connected into the radio jack. Check to ensure that the antenna is properly installed on radio. Inspect the antenna for any signs of damage. If any damage is found, the antenna will need to be replaced.  If problems persist, please contact Support