Short communication range or poor audio.

Analysis
1, The connecting cable is damaged, and the signal energy leaks.
2,The antenna connector and the cable may get loose connection or even disconnected.
3, Invisible damage may occur to the cable.
4, Duplexer is not properly set (if the duplexer is mounted).
Solution
1, Check the damages, and replace the cable with a new one if necessary.
2, Check and secure the cable connector, or replace it if necessary.
3, Replace the cable with a new one.
4. Contact the manufacturer or your dealer to re-set the duplexer.