I read somewhere its due to phone freezing on mute state so its dead silence on the either end. Would you please perform following two possible solution if they really work for us or not?
1. While calling if there is dead silence please consider clicking volume up and down button. It might trigger our device from mute state.
2. Consider keeping the volume one click below the max as number of people has mentioned that had help them to avoid the issue.
Please let me know if these solution does help you.
P.S: I would have done it by myself but i don't have moto g at the moment.
Best of luck.
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