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2. The auxiliary machine plug or DC power plug is loose. Please insert it tightly.
3, the volume knob is not adjusted, adjustable knob. 
4. In order to prevent the intercom host and the sub machine from falling off, the BNC interface can be tightened. 
2. Howling 1. The soundproofing performance of the installation environment is too bad. The distance between the host and the auxiliary machine should be further extended.
2, the environment noise, the volume knob to reduce the appropriate number. 
3, for example: Prototype testing should be opened a certain distance; such a noisy environment noise effect is not as closed as the counter, it is best to get the business counter to test, adjust the volume knob to 4 position volume effect will be better.
Third, the teller listens too loudly. 1. The volume knob is too small to turn clockwise.
2, the customer is too far away from the auxiliary machine, please be closer.
Fourth, the client listens to the sound too little sound 1. The tubular microphone does not point to the teller and should be facing the teller.
2. The external volume knob is too small to turn clockwise. 
5. When the sound is intermittent, it cannot even be transmitted. 1. The speaker is too far away from the microphone and should be closer to the microphone (less than 1250px ideal).
2. When one party is talking, the other party will be squashed.
3, the ambient noise is too strong, you can turn down the volume knob of the corresponding channel, or ask the speaker to be closer to the microphone.
Window Intercom General Troubleshooting Methods
One, silent 1,220V power is plugged in, should plug in the power supply.