If the level of noise from Zello to Radio is very high, this could be a sign that the PC audio output overloads the audio input of the radio. You need to carefully decrease volume levels until the distorted audio is eliminated.
The easiest way to do it is as follows:
1. Plug in a headset to a test radio. Please make sure there are no other radios in the room other than the donor radio connected to the gateway. This will guarantee acoustic feedback doesn't interfere.
2. Set volume on the test radio to a comfortable level. Ask someone to transmit from a third radio outside of the room. You should be able to hear transmissions from other radios clearly.
3. If you changed the Playback amplifier setting in Zello, change it back to 0 dB. Simply go to Tools>Options>Audio
4. Make a test call with silent audio from a device with the ZelloWork app (i.e. a cell phone or tablet) to the gateway. If you don't have the donor radio connected to the gateway, please connect it now.
- To create silent audio on a device go to Menu > Options/Settings > Audio and set the Recording amplifier to -20 dB.
- Send a message from the device to the gateway. Don't use a channel, but instead send to the gateway directly. You should get a transmission which is very silent with minimal radio noise.
- If you get high level of noise you need to troubleshoot before going further. The most common source of noise will be interference from electrical equipment near the radio and the gateway. Try moving the cables away while sending a message to the gateway in order to observe if the noise changes.
5. Once you get a good silent transmission working with an acceptable level of noise, change the Recording amplifier setting on your device back to 0 dB and try again.
6. If you still get lots of noise proceed to adjust the volume on the device
7. Set the Playback device volume to 1/4 of the full value -- this should give you undistorted voice which will probably be very quiet
8. Adjust the volume up slowly until the sound starts to distort, and then adjust a little back.
9. If you adjusted it all the way up and there is still no distortion (and volume is still too low), start adjusting the Playback amplifier.
Questions? Email [email protected] for more information.