Many owners of the Samsung Galaxy Note 3 have faced phone call problems of not being able to hear on both sides, at random times. One person said, “It seems to be happening with both landline and cell phones – periodically when sending or receiving a call I can’t hear the person and they can’t hear me. If I call them back or they call me back it works fine again”
Firstly, the issue could be either hardware or software. Since this is happening irregularly and with random callers. Try pulling the battery out and rebooting the device. If the problem still persists, backup your Note 3 and perform a factory reset by going to Settings, General, Back and Reset, Factory Reset.
This would restore the device to its factory settings. Check if the Note 3 continues to exhibit similar phone call problems. If so, there could be a problem with the hardware, related to the software not working properly to make the call. If so, take your Note 3 to a Samsung Customer Care and fix it if you have warranty left, assuming you have not rooted it.
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